Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/kernel/sys.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | */ | |
6 | ||
9984de1a | 7 | #include <linux/export.h> |
1da177e4 LT |
8 | #include <linux/mm.h> |
9 | #include <linux/utsname.h> | |
10 | #include <linux/mman.h> | |
1da177e4 LT |
11 | #include <linux/reboot.h> |
12 | #include <linux/prctl.h> | |
1da177e4 LT |
13 | #include <linux/highuid.h> |
14 | #include <linux/fs.h> | |
74da1ff7 | 15 | #include <linux/kmod.h> |
cdd6c482 | 16 | #include <linux/perf_event.h> |
3e88c553 | 17 | #include <linux/resource.h> |
dc009d92 EB |
18 | #include <linux/kernel.h> |
19 | #include <linux/kexec.h> | |
1da177e4 | 20 | #include <linux/workqueue.h> |
c59ede7b | 21 | #include <linux/capability.h> |
1da177e4 LT |
22 | #include <linux/device.h> |
23 | #include <linux/key.h> | |
24 | #include <linux/times.h> | |
25 | #include <linux/posix-timers.h> | |
26 | #include <linux/security.h> | |
27 | #include <linux/dcookies.h> | |
28 | #include <linux/suspend.h> | |
29 | #include <linux/tty.h> | |
7ed20e1a | 30 | #include <linux/signal.h> |
9f46080c | 31 | #include <linux/cn_proc.h> |
3cfc348b | 32 | #include <linux/getcpu.h> |
6eaeeaba | 33 | #include <linux/task_io_accounting_ops.h> |
1d9d02fe | 34 | #include <linux/seccomp.h> |
4047727e | 35 | #include <linux/cpu.h> |
e28cbf22 | 36 | #include <linux/personality.h> |
e3d5a27d | 37 | #include <linux/ptrace.h> |
5ad4e53b | 38 | #include <linux/fs_struct.h> |
b32dfe37 CG |
39 | #include <linux/file.h> |
40 | #include <linux/mount.h> | |
5a0e3ad6 | 41 | #include <linux/gfp.h> |
40dc166c | 42 | #include <linux/syscore_ops.h> |
be27425d AK |
43 | #include <linux/version.h> |
44 | #include <linux/ctype.h> | |
1da177e4 LT |
45 | |
46 | #include <linux/compat.h> | |
47 | #include <linux/syscalls.h> | |
00d7c05a | 48 | #include <linux/kprobes.h> |
acce292c | 49 | #include <linux/user_namespace.h> |
7fe5e042 | 50 | #include <linux/binfmts.h> |
1da177e4 | 51 | |
4a22f166 SR |
52 | #include <linux/sched.h> |
53 | #include <linux/rcupdate.h> | |
54 | #include <linux/uidgid.h> | |
55 | #include <linux/cred.h> | |
56 | ||
04c6862c | 57 | #include <linux/kmsg_dump.h> |
be27425d AK |
58 | /* Move somewhere else to avoid recompiling? */ |
59 | #include <generated/utsrelease.h> | |
04c6862c | 60 | |
1da177e4 LT |
61 | #include <asm/uaccess.h> |
62 | #include <asm/io.h> | |
63 | #include <asm/unistd.h> | |
64 | ||
65 | #ifndef SET_UNALIGN_CTL | |
66 | # define SET_UNALIGN_CTL(a,b) (-EINVAL) | |
67 | #endif | |
68 | #ifndef GET_UNALIGN_CTL | |
69 | # define GET_UNALIGN_CTL(a,b) (-EINVAL) | |
70 | #endif | |
71 | #ifndef SET_FPEMU_CTL | |
72 | # define SET_FPEMU_CTL(a,b) (-EINVAL) | |
73 | #endif | |
74 | #ifndef GET_FPEMU_CTL | |
75 | # define GET_FPEMU_CTL(a,b) (-EINVAL) | |
76 | #endif | |
77 | #ifndef SET_FPEXC_CTL | |
78 | # define SET_FPEXC_CTL(a,b) (-EINVAL) | |
79 | #endif | |
80 | #ifndef GET_FPEXC_CTL | |
81 | # define GET_FPEXC_CTL(a,b) (-EINVAL) | |
82 | #endif | |
651d765d AB |
83 | #ifndef GET_ENDIAN |
84 | # define GET_ENDIAN(a,b) (-EINVAL) | |
85 | #endif | |
86 | #ifndef SET_ENDIAN | |
87 | # define SET_ENDIAN(a,b) (-EINVAL) | |
88 | #endif | |
8fb402bc EB |
89 | #ifndef GET_TSC_CTL |
90 | # define GET_TSC_CTL(a) (-EINVAL) | |
91 | #endif | |
92 | #ifndef SET_TSC_CTL | |
93 | # define SET_TSC_CTL(a) (-EINVAL) | |
94 | #endif | |
1da177e4 LT |
95 | |
96 | /* | |
97 | * this is where the system-wide overflow UID and GID are defined, for | |
98 | * architectures that now have 32-bit UID/GID but didn't in the past | |
99 | */ | |
100 | ||
101 | int overflowuid = DEFAULT_OVERFLOWUID; | |
102 | int overflowgid = DEFAULT_OVERFLOWGID; | |
103 | ||
1da177e4 LT |
104 | EXPORT_SYMBOL(overflowuid); |
105 | EXPORT_SYMBOL(overflowgid); | |
1da177e4 LT |
106 | |
107 | /* | |
108 | * the same as above, but for filesystems which can only store a 16-bit | |
109 | * UID and GID. as such, this is needed on all architectures | |
110 | */ | |
111 | ||
112 | int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; | |
113 | int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; | |
114 | ||
115 | EXPORT_SYMBOL(fs_overflowuid); | |
116 | EXPORT_SYMBOL(fs_overflowgid); | |
117 | ||
118 | /* | |
119 | * this indicates whether you can reboot with ctrl-alt-del: the default is yes | |
120 | */ | |
121 | ||
122 | int C_A_D = 1; | |
9ec52099 CLG |
123 | struct pid *cad_pid; |
124 | EXPORT_SYMBOL(cad_pid); | |
1da177e4 | 125 | |
bd804eba RW |
126 | /* |
127 | * If set, this is used for preparing the system to power off. | |
128 | */ | |
129 | ||
130 | void (*pm_power_off_prepare)(void); | |
bd804eba | 131 | |
fc832ad3 SH |
132 | /* |
133 | * Returns true if current's euid is same as p's uid or euid, | |
134 | * or has CAP_SYS_NICE to p's user_ns. | |
135 | * | |
136 | * Called with rcu_read_lock, creds are safe | |
137 | */ | |
138 | static bool set_one_prio_perm(struct task_struct *p) | |
139 | { | |
140 | const struct cred *cred = current_cred(), *pcred = __task_cred(p); | |
141 | ||
5af66203 EB |
142 | if (uid_eq(pcred->uid, cred->euid) || |
143 | uid_eq(pcred->euid, cred->euid)) | |
fc832ad3 | 144 | return true; |
c4a4d603 | 145 | if (ns_capable(pcred->user_ns, CAP_SYS_NICE)) |
fc832ad3 SH |
146 | return true; |
147 | return false; | |
148 | } | |
149 | ||
c69e8d9c DH |
150 | /* |
151 | * set the priority of a task | |
152 | * - the caller must hold the RCU read lock | |
153 | */ | |
1da177e4 LT |
154 | static int set_one_prio(struct task_struct *p, int niceval, int error) |
155 | { | |
156 | int no_nice; | |
157 | ||
fc832ad3 | 158 | if (!set_one_prio_perm(p)) { |
1da177e4 LT |
159 | error = -EPERM; |
160 | goto out; | |
161 | } | |
e43379f1 | 162 | if (niceval < task_nice(p) && !can_nice(p, niceval)) { |
1da177e4 LT |
163 | error = -EACCES; |
164 | goto out; | |
165 | } | |
166 | no_nice = security_task_setnice(p, niceval); | |
167 | if (no_nice) { | |
168 | error = no_nice; | |
169 | goto out; | |
170 | } | |
171 | if (error == -ESRCH) | |
172 | error = 0; | |
173 | set_user_nice(p, niceval); | |
174 | out: | |
175 | return error; | |
176 | } | |
177 | ||
754fe8d2 | 178 | SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval) |
1da177e4 LT |
179 | { |
180 | struct task_struct *g, *p; | |
181 | struct user_struct *user; | |
86a264ab | 182 | const struct cred *cred = current_cred(); |
1da177e4 | 183 | int error = -EINVAL; |
41487c65 | 184 | struct pid *pgrp; |
7b44ab97 | 185 | kuid_t uid; |
1da177e4 | 186 | |
3e88c553 | 187 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
188 | goto out; |
189 | ||
190 | /* normalize: avoid signed division (rounding problems) */ | |
191 | error = -ESRCH; | |
192 | if (niceval < -20) | |
193 | niceval = -20; | |
194 | if (niceval > 19) | |
195 | niceval = 19; | |
196 | ||
d4581a23 | 197 | rcu_read_lock(); |
1da177e4 LT |
198 | read_lock(&tasklist_lock); |
199 | switch (which) { | |
200 | case PRIO_PROCESS: | |
41487c65 | 201 | if (who) |
228ebcbe | 202 | p = find_task_by_vpid(who); |
41487c65 EB |
203 | else |
204 | p = current; | |
1da177e4 LT |
205 | if (p) |
206 | error = set_one_prio(p, niceval, error); | |
207 | break; | |
208 | case PRIO_PGRP: | |
41487c65 | 209 | if (who) |
b488893a | 210 | pgrp = find_vpid(who); |
41487c65 EB |
211 | else |
212 | pgrp = task_pgrp(current); | |
2d70b68d | 213 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 | 214 | error = set_one_prio(p, niceval, error); |
2d70b68d | 215 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
216 | break; |
217 | case PRIO_USER: | |
7b44ab97 | 218 | uid = make_kuid(cred->user_ns, who); |
74ba508f | 219 | user = cred->user; |
1da177e4 | 220 | if (!who) |
078de5f7 EB |
221 | uid = cred->uid; |
222 | else if (!uid_eq(uid, cred->uid) && | |
7b44ab97 | 223 | !(user = find_user(uid))) |
86a264ab | 224 | goto out_unlock; /* No processes for this user */ |
1da177e4 | 225 | |
dfc6a736 | 226 | do_each_thread(g, p) { |
078de5f7 | 227 | if (uid_eq(task_uid(p), uid)) |
1da177e4 | 228 | error = set_one_prio(p, niceval, error); |
dfc6a736 | 229 | } while_each_thread(g, p); |
078de5f7 | 230 | if (!uid_eq(uid, cred->uid)) |
1da177e4 LT |
231 | free_uid(user); /* For find_user() */ |
232 | break; | |
233 | } | |
234 | out_unlock: | |
235 | read_unlock(&tasklist_lock); | |
d4581a23 | 236 | rcu_read_unlock(); |
1da177e4 LT |
237 | out: |
238 | return error; | |
239 | } | |
240 | ||
241 | /* | |
242 | * Ugh. To avoid negative return values, "getpriority()" will | |
243 | * not return the normal nice-value, but a negated value that | |
244 | * has been offset by 20 (ie it returns 40..1 instead of -20..19) | |
245 | * to stay compatible. | |
246 | */ | |
754fe8d2 | 247 | SYSCALL_DEFINE2(getpriority, int, which, int, who) |
1da177e4 LT |
248 | { |
249 | struct task_struct *g, *p; | |
250 | struct user_struct *user; | |
86a264ab | 251 | const struct cred *cred = current_cred(); |
1da177e4 | 252 | long niceval, retval = -ESRCH; |
41487c65 | 253 | struct pid *pgrp; |
7b44ab97 | 254 | kuid_t uid; |
1da177e4 | 255 | |
3e88c553 | 256 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
257 | return -EINVAL; |
258 | ||
70118837 | 259 | rcu_read_lock(); |
1da177e4 LT |
260 | read_lock(&tasklist_lock); |
261 | switch (which) { | |
262 | case PRIO_PROCESS: | |
41487c65 | 263 | if (who) |
228ebcbe | 264 | p = find_task_by_vpid(who); |
41487c65 EB |
265 | else |
266 | p = current; | |
1da177e4 LT |
267 | if (p) { |
268 | niceval = 20 - task_nice(p); | |
269 | if (niceval > retval) | |
270 | retval = niceval; | |
271 | } | |
272 | break; | |
273 | case PRIO_PGRP: | |
41487c65 | 274 | if (who) |
b488893a | 275 | pgrp = find_vpid(who); |
41487c65 EB |
276 | else |
277 | pgrp = task_pgrp(current); | |
2d70b68d | 278 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 LT |
279 | niceval = 20 - task_nice(p); |
280 | if (niceval > retval) | |
281 | retval = niceval; | |
2d70b68d | 282 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
283 | break; |
284 | case PRIO_USER: | |
7b44ab97 | 285 | uid = make_kuid(cred->user_ns, who); |
74ba508f | 286 | user = cred->user; |
1da177e4 | 287 | if (!who) |
078de5f7 EB |
288 | uid = cred->uid; |
289 | else if (!uid_eq(uid, cred->uid) && | |
7b44ab97 | 290 | !(user = find_user(uid))) |
86a264ab | 291 | goto out_unlock; /* No processes for this user */ |
1da177e4 | 292 | |
dfc6a736 | 293 | do_each_thread(g, p) { |
078de5f7 | 294 | if (uid_eq(task_uid(p), uid)) { |
1da177e4 LT |
295 | niceval = 20 - task_nice(p); |
296 | if (niceval > retval) | |
297 | retval = niceval; | |
298 | } | |
dfc6a736 | 299 | } while_each_thread(g, p); |
078de5f7 | 300 | if (!uid_eq(uid, cred->uid)) |
1da177e4 LT |
301 | free_uid(user); /* for find_user() */ |
302 | break; | |
303 | } | |
304 | out_unlock: | |
305 | read_unlock(&tasklist_lock); | |
70118837 | 306 | rcu_read_unlock(); |
1da177e4 LT |
307 | |
308 | return retval; | |
309 | } | |
310 | ||
e4c94330 EB |
311 | /** |
312 | * emergency_restart - reboot the system | |
313 | * | |
314 | * Without shutting down any hardware or taking any locks | |
315 | * reboot the system. This is called when we know we are in | |
316 | * trouble so this is our best effort to reboot. This is | |
317 | * safe to call in interrupt context. | |
318 | */ | |
7c903473 EB |
319 | void emergency_restart(void) |
320 | { | |
04c6862c | 321 | kmsg_dump(KMSG_DUMP_EMERG); |
7c903473 EB |
322 | machine_emergency_restart(); |
323 | } | |
324 | EXPORT_SYMBOL_GPL(emergency_restart); | |
325 | ||
ca195b7f | 326 | void kernel_restart_prepare(char *cmd) |
4a00ea1e | 327 | { |
e041c683 | 328 | blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd); |
4a00ea1e | 329 | system_state = SYSTEM_RESTART; |
b50fa7c8 | 330 | usermodehelper_disable(); |
4a00ea1e | 331 | device_shutdown(); |
e4c94330 | 332 | } |
1e5d5331 | 333 | |
c5f41752 AW |
334 | /** |
335 | * register_reboot_notifier - Register function to be called at reboot time | |
336 | * @nb: Info about notifier function to be called | |
337 | * | |
338 | * Registers a function with the list of functions | |
339 | * to be called at reboot time. | |
340 | * | |
341 | * Currently always returns zero, as blocking_notifier_chain_register() | |
342 | * always returns zero. | |
343 | */ | |
344 | int register_reboot_notifier(struct notifier_block *nb) | |
345 | { | |
346 | return blocking_notifier_chain_register(&reboot_notifier_list, nb); | |
347 | } | |
348 | EXPORT_SYMBOL(register_reboot_notifier); | |
349 | ||
350 | /** | |
351 | * unregister_reboot_notifier - Unregister previously registered reboot notifier | |
352 | * @nb: Hook to be unregistered | |
353 | * | |
354 | * Unregisters a previously registered reboot | |
355 | * notifier function. | |
356 | * | |
357 | * Returns zero on success, or %-ENOENT on failure. | |
358 | */ | |
359 | int unregister_reboot_notifier(struct notifier_block *nb) | |
360 | { | |
361 | return blocking_notifier_chain_unregister(&reboot_notifier_list, nb); | |
362 | } | |
363 | EXPORT_SYMBOL(unregister_reboot_notifier); | |
364 | ||
1e5d5331 RD |
365 | /** |
366 | * kernel_restart - reboot the system | |
367 | * @cmd: pointer to buffer containing command to execute for restart | |
b8887e6e | 368 | * or %NULL |
1e5d5331 RD |
369 | * |
370 | * Shutdown everything and perform a clean reboot. | |
371 | * This is not safe to call in interrupt context. | |
372 | */ | |
e4c94330 EB |
373 | void kernel_restart(char *cmd) |
374 | { | |
375 | kernel_restart_prepare(cmd); | |
f96972f2 | 376 | disable_nonboot_cpus(); |
6f389a8f | 377 | syscore_shutdown(); |
756184b7 | 378 | if (!cmd) |
4a00ea1e | 379 | printk(KERN_EMERG "Restarting system.\n"); |
756184b7 | 380 | else |
4a00ea1e | 381 | printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd); |
04c6862c | 382 | kmsg_dump(KMSG_DUMP_RESTART); |
4a00ea1e EB |
383 | machine_restart(cmd); |
384 | } | |
385 | EXPORT_SYMBOL_GPL(kernel_restart); | |
386 | ||
4ef7229f | 387 | static void kernel_shutdown_prepare(enum system_states state) |
729b4d4c | 388 | { |
e041c683 | 389 | blocking_notifier_call_chain(&reboot_notifier_list, |
729b4d4c AS |
390 | (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL); |
391 | system_state = state; | |
b50fa7c8 | 392 | usermodehelper_disable(); |
729b4d4c AS |
393 | device_shutdown(); |
394 | } | |
e4c94330 EB |
395 | /** |
396 | * kernel_halt - halt the system | |
397 | * | |
398 | * Shutdown everything and perform a clean system halt. | |
399 | */ | |
e4c94330 EB |
400 | void kernel_halt(void) |
401 | { | |
729b4d4c | 402 | kernel_shutdown_prepare(SYSTEM_HALT); |
6f389a8f | 403 | disable_nonboot_cpus(); |
40dc166c | 404 | syscore_shutdown(); |
4a00ea1e | 405 | printk(KERN_EMERG "System halted.\n"); |
04c6862c | 406 | kmsg_dump(KMSG_DUMP_HALT); |
4a00ea1e EB |
407 | machine_halt(); |
408 | } | |
729b4d4c | 409 | |
4a00ea1e EB |
410 | EXPORT_SYMBOL_GPL(kernel_halt); |
411 | ||
e4c94330 EB |
412 | /** |
413 | * kernel_power_off - power_off the system | |
414 | * | |
415 | * Shutdown everything and perform a clean system power_off. | |
416 | */ | |
e4c94330 EB |
417 | void kernel_power_off(void) |
418 | { | |
729b4d4c | 419 | kernel_shutdown_prepare(SYSTEM_POWER_OFF); |
bd804eba RW |
420 | if (pm_power_off_prepare) |
421 | pm_power_off_prepare(); | |
4047727e | 422 | disable_nonboot_cpus(); |
40dc166c | 423 | syscore_shutdown(); |
4a00ea1e | 424 | printk(KERN_EMERG "Power down.\n"); |
04c6862c | 425 | kmsg_dump(KMSG_DUMP_POWEROFF); |
4a00ea1e EB |
426 | machine_power_off(); |
427 | } | |
428 | EXPORT_SYMBOL_GPL(kernel_power_off); | |
6f15fa50 TG |
429 | |
430 | static DEFINE_MUTEX(reboot_mutex); | |
431 | ||
1da177e4 LT |
432 | /* |
433 | * Reboot system call: for obvious reasons only root may call it, | |
434 | * and even root needs to set up some magic numbers in the registers | |
435 | * so that some mistake won't make this reboot the whole machine. | |
436 | * You can also set the meaning of the ctrl-alt-del-key here. | |
437 | * | |
438 | * reboot doesn't sync: do that yourself before calling this. | |
439 | */ | |
754fe8d2 HC |
440 | SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, |
441 | void __user *, arg) | |
1da177e4 | 442 | { |
923c7538 | 443 | struct pid_namespace *pid_ns = task_active_pid_ns(current); |
1da177e4 | 444 | char buffer[256]; |
3d26dcf7 | 445 | int ret = 0; |
1da177e4 LT |
446 | |
447 | /* We only trust the superuser with rebooting the system. */ | |
923c7538 | 448 | if (!ns_capable(pid_ns->user_ns, CAP_SYS_BOOT)) |
1da177e4 LT |
449 | return -EPERM; |
450 | ||
451 | /* For safety, we require "magic" arguments. */ | |
452 | if (magic1 != LINUX_REBOOT_MAGIC1 || | |
453 | (magic2 != LINUX_REBOOT_MAGIC2 && | |
454 | magic2 != LINUX_REBOOT_MAGIC2A && | |
455 | magic2 != LINUX_REBOOT_MAGIC2B && | |
456 | magic2 != LINUX_REBOOT_MAGIC2C)) | |
457 | return -EINVAL; | |
458 | ||
cf3f8921 DL |
459 | /* |
460 | * If pid namespaces are enabled and the current task is in a child | |
461 | * pid_namespace, the command is handled by reboot_pid_ns() which will | |
462 | * call do_exit(). | |
463 | */ | |
923c7538 | 464 | ret = reboot_pid_ns(pid_ns, cmd); |
cf3f8921 DL |
465 | if (ret) |
466 | return ret; | |
467 | ||
5e38291d EB |
468 | /* Instead of trying to make the power_off code look like |
469 | * halt when pm_power_off is not set do it the easy way. | |
470 | */ | |
471 | if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off) | |
472 | cmd = LINUX_REBOOT_CMD_HALT; | |
473 | ||
6f15fa50 | 474 | mutex_lock(&reboot_mutex); |
1da177e4 LT |
475 | switch (cmd) { |
476 | case LINUX_REBOOT_CMD_RESTART: | |
4a00ea1e | 477 | kernel_restart(NULL); |
1da177e4 LT |
478 | break; |
479 | ||
480 | case LINUX_REBOOT_CMD_CAD_ON: | |
481 | C_A_D = 1; | |
482 | break; | |
483 | ||
484 | case LINUX_REBOOT_CMD_CAD_OFF: | |
485 | C_A_D = 0; | |
486 | break; | |
487 | ||
488 | case LINUX_REBOOT_CMD_HALT: | |
4a00ea1e | 489 | kernel_halt(); |
1da177e4 | 490 | do_exit(0); |
3d26dcf7 | 491 | panic("cannot halt"); |
1da177e4 LT |
492 | |
493 | case LINUX_REBOOT_CMD_POWER_OFF: | |
4a00ea1e | 494 | kernel_power_off(); |
1da177e4 LT |
495 | do_exit(0); |
496 | break; | |
497 | ||
498 | case LINUX_REBOOT_CMD_RESTART2: | |
499 | if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) { | |
6f15fa50 TG |
500 | ret = -EFAULT; |
501 | break; | |
1da177e4 LT |
502 | } |
503 | buffer[sizeof(buffer) - 1] = '\0'; | |
504 | ||
4a00ea1e | 505 | kernel_restart(buffer); |
1da177e4 LT |
506 | break; |
507 | ||
3ab83521 | 508 | #ifdef CONFIG_KEXEC |
dc009d92 | 509 | case LINUX_REBOOT_CMD_KEXEC: |
3d26dcf7 AK |
510 | ret = kernel_kexec(); |
511 | break; | |
3ab83521 | 512 | #endif |
4a00ea1e | 513 | |
b0cb1a19 | 514 | #ifdef CONFIG_HIBERNATION |
1da177e4 | 515 | case LINUX_REBOOT_CMD_SW_SUSPEND: |
3d26dcf7 AK |
516 | ret = hibernate(); |
517 | break; | |
1da177e4 LT |
518 | #endif |
519 | ||
520 | default: | |
3d26dcf7 AK |
521 | ret = -EINVAL; |
522 | break; | |
1da177e4 | 523 | } |
6f15fa50 | 524 | mutex_unlock(&reboot_mutex); |
3d26dcf7 | 525 | return ret; |
1da177e4 LT |
526 | } |
527 | ||
65f27f38 | 528 | static void deferred_cad(struct work_struct *dummy) |
1da177e4 | 529 | { |
abcd9e51 | 530 | kernel_restart(NULL); |
1da177e4 LT |
531 | } |
532 | ||
533 | /* | |
534 | * This function gets called by ctrl-alt-del - ie the keyboard interrupt. | |
535 | * As it's called within an interrupt, it may NOT sync: the only choice | |
536 | * is whether to reboot at once, or just ignore the ctrl-alt-del. | |
537 | */ | |
538 | void ctrl_alt_del(void) | |
539 | { | |
65f27f38 | 540 | static DECLARE_WORK(cad_work, deferred_cad); |
1da177e4 LT |
541 | |
542 | if (C_A_D) | |
543 | schedule_work(&cad_work); | |
544 | else | |
9ec52099 | 545 | kill_cad_pid(SIGINT, 1); |
1da177e4 LT |
546 | } |
547 | ||
1da177e4 LT |
548 | /* |
549 | * Unprivileged users may change the real gid to the effective gid | |
550 | * or vice versa. (BSD-style) | |
551 | * | |
552 | * If you set the real gid at all, or set the effective gid to a value not | |
553 | * equal to the real gid, then the saved gid is set to the new effective gid. | |
554 | * | |
555 | * This makes it possible for a setgid program to completely drop its | |
556 | * privileges, which is often a useful assertion to make when you are doing | |
557 | * a security audit over a program. | |
558 | * | |
559 | * The general idea is that a program which uses just setregid() will be | |
560 | * 100% compatible with BSD. A program which uses just setgid() will be | |
561 | * 100% compatible with POSIX with saved IDs. | |
562 | * | |
563 | * SMP: There are not races, the GIDs are checked only by filesystem | |
564 | * operations (as far as semantic preservation is concerned). | |
565 | */ | |
ae1251ab | 566 | SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) |
1da177e4 | 567 | { |
a29c33f4 | 568 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
569 | const struct cred *old; |
570 | struct cred *new; | |
1da177e4 | 571 | int retval; |
a29c33f4 EB |
572 | kgid_t krgid, kegid; |
573 | ||
574 | krgid = make_kgid(ns, rgid); | |
575 | kegid = make_kgid(ns, egid); | |
576 | ||
577 | if ((rgid != (gid_t) -1) && !gid_valid(krgid)) | |
578 | return -EINVAL; | |
579 | if ((egid != (gid_t) -1) && !gid_valid(kegid)) | |
580 | return -EINVAL; | |
1da177e4 | 581 | |
d84f4f99 DH |
582 | new = prepare_creds(); |
583 | if (!new) | |
584 | return -ENOMEM; | |
585 | old = current_cred(); | |
586 | ||
d84f4f99 | 587 | retval = -EPERM; |
1da177e4 | 588 | if (rgid != (gid_t) -1) { |
a29c33f4 EB |
589 | if (gid_eq(old->gid, krgid) || |
590 | gid_eq(old->egid, krgid) || | |
fc832ad3 | 591 | nsown_capable(CAP_SETGID)) |
a29c33f4 | 592 | new->gid = krgid; |
1da177e4 | 593 | else |
d84f4f99 | 594 | goto error; |
1da177e4 LT |
595 | } |
596 | if (egid != (gid_t) -1) { | |
a29c33f4 EB |
597 | if (gid_eq(old->gid, kegid) || |
598 | gid_eq(old->egid, kegid) || | |
599 | gid_eq(old->sgid, kegid) || | |
fc832ad3 | 600 | nsown_capable(CAP_SETGID)) |
a29c33f4 | 601 | new->egid = kegid; |
756184b7 | 602 | else |
d84f4f99 | 603 | goto error; |
1da177e4 | 604 | } |
d84f4f99 | 605 | |
1da177e4 | 606 | if (rgid != (gid_t) -1 || |
a29c33f4 | 607 | (egid != (gid_t) -1 && !gid_eq(kegid, old->gid))) |
d84f4f99 DH |
608 | new->sgid = new->egid; |
609 | new->fsgid = new->egid; | |
610 | ||
611 | return commit_creds(new); | |
612 | ||
613 | error: | |
614 | abort_creds(new); | |
615 | return retval; | |
1da177e4 LT |
616 | } |
617 | ||
618 | /* | |
619 | * setgid() is implemented like SysV w/ SAVED_IDS | |
620 | * | |
621 | * SMP: Same implicit races as above. | |
622 | */ | |
ae1251ab | 623 | SYSCALL_DEFINE1(setgid, gid_t, gid) |
1da177e4 | 624 | { |
a29c33f4 | 625 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
626 | const struct cred *old; |
627 | struct cred *new; | |
1da177e4 | 628 | int retval; |
a29c33f4 EB |
629 | kgid_t kgid; |
630 | ||
631 | kgid = make_kgid(ns, gid); | |
632 | if (!gid_valid(kgid)) | |
633 | return -EINVAL; | |
1da177e4 | 634 | |
d84f4f99 DH |
635 | new = prepare_creds(); |
636 | if (!new) | |
637 | return -ENOMEM; | |
638 | old = current_cred(); | |
639 | ||
d84f4f99 | 640 | retval = -EPERM; |
fc832ad3 | 641 | if (nsown_capable(CAP_SETGID)) |
a29c33f4 EB |
642 | new->gid = new->egid = new->sgid = new->fsgid = kgid; |
643 | else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid)) | |
644 | new->egid = new->fsgid = kgid; | |
1da177e4 | 645 | else |
d84f4f99 | 646 | goto error; |
1da177e4 | 647 | |
d84f4f99 DH |
648 | return commit_creds(new); |
649 | ||
650 | error: | |
651 | abort_creds(new); | |
652 | return retval; | |
1da177e4 | 653 | } |
54e99124 | 654 | |
d84f4f99 DH |
655 | /* |
656 | * change the user struct in a credentials set to match the new UID | |
657 | */ | |
658 | static int set_user(struct cred *new) | |
1da177e4 LT |
659 | { |
660 | struct user_struct *new_user; | |
661 | ||
078de5f7 | 662 | new_user = alloc_uid(new->uid); |
1da177e4 LT |
663 | if (!new_user) |
664 | return -EAGAIN; | |
665 | ||
72fa5997 VK |
666 | /* |
667 | * We don't fail in case of NPROC limit excess here because too many | |
668 | * poorly written programs don't check set*uid() return code, assuming | |
669 | * it never fails if called by root. We may still enforce NPROC limit | |
670 | * for programs doing set*uid()+execve() by harmlessly deferring the | |
671 | * failure to the execve() stage. | |
672 | */ | |
78d7d407 | 673 | if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) && |
72fa5997 VK |
674 | new_user != INIT_USER) |
675 | current->flags |= PF_NPROC_EXCEEDED; | |
676 | else | |
677 | current->flags &= ~PF_NPROC_EXCEEDED; | |
1da177e4 | 678 | |
d84f4f99 DH |
679 | free_uid(new->user); |
680 | new->user = new_user; | |
1da177e4 LT |
681 | return 0; |
682 | } | |
683 | ||
684 | /* | |
685 | * Unprivileged users may change the real uid to the effective uid | |
686 | * or vice versa. (BSD-style) | |
687 | * | |
688 | * If you set the real uid at all, or set the effective uid to a value not | |
689 | * equal to the real uid, then the saved uid is set to the new effective uid. | |
690 | * | |
691 | * This makes it possible for a setuid program to completely drop its | |
692 | * privileges, which is often a useful assertion to make when you are doing | |
693 | * a security audit over a program. | |
694 | * | |
695 | * The general idea is that a program which uses just setreuid() will be | |
696 | * 100% compatible with BSD. A program which uses just setuid() will be | |
697 | * 100% compatible with POSIX with saved IDs. | |
698 | */ | |
ae1251ab | 699 | SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) |
1da177e4 | 700 | { |
a29c33f4 | 701 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
702 | const struct cred *old; |
703 | struct cred *new; | |
1da177e4 | 704 | int retval; |
a29c33f4 EB |
705 | kuid_t kruid, keuid; |
706 | ||
707 | kruid = make_kuid(ns, ruid); | |
708 | keuid = make_kuid(ns, euid); | |
709 | ||
710 | if ((ruid != (uid_t) -1) && !uid_valid(kruid)) | |
711 | return -EINVAL; | |
712 | if ((euid != (uid_t) -1) && !uid_valid(keuid)) | |
713 | return -EINVAL; | |
1da177e4 | 714 | |
d84f4f99 DH |
715 | new = prepare_creds(); |
716 | if (!new) | |
717 | return -ENOMEM; | |
718 | old = current_cred(); | |
719 | ||
d84f4f99 | 720 | retval = -EPERM; |
1da177e4 | 721 | if (ruid != (uid_t) -1) { |
a29c33f4 EB |
722 | new->uid = kruid; |
723 | if (!uid_eq(old->uid, kruid) && | |
724 | !uid_eq(old->euid, kruid) && | |
fc832ad3 | 725 | !nsown_capable(CAP_SETUID)) |
d84f4f99 | 726 | goto error; |
1da177e4 LT |
727 | } |
728 | ||
729 | if (euid != (uid_t) -1) { | |
a29c33f4 EB |
730 | new->euid = keuid; |
731 | if (!uid_eq(old->uid, keuid) && | |
732 | !uid_eq(old->euid, keuid) && | |
733 | !uid_eq(old->suid, keuid) && | |
fc832ad3 | 734 | !nsown_capable(CAP_SETUID)) |
d84f4f99 | 735 | goto error; |
1da177e4 LT |
736 | } |
737 | ||
a29c33f4 | 738 | if (!uid_eq(new->uid, old->uid)) { |
54e99124 DG |
739 | retval = set_user(new); |
740 | if (retval < 0) | |
741 | goto error; | |
742 | } | |
1da177e4 | 743 | if (ruid != (uid_t) -1 || |
a29c33f4 | 744 | (euid != (uid_t) -1 && !uid_eq(keuid, old->uid))) |
d84f4f99 DH |
745 | new->suid = new->euid; |
746 | new->fsuid = new->euid; | |
1da177e4 | 747 | |
d84f4f99 DH |
748 | retval = security_task_fix_setuid(new, old, LSM_SETID_RE); |
749 | if (retval < 0) | |
750 | goto error; | |
1da177e4 | 751 | |
d84f4f99 | 752 | return commit_creds(new); |
1da177e4 | 753 | |
d84f4f99 DH |
754 | error: |
755 | abort_creds(new); | |
756 | return retval; | |
757 | } | |
1da177e4 LT |
758 | |
759 | /* | |
760 | * setuid() is implemented like SysV with SAVED_IDS | |
761 | * | |
762 | * Note that SAVED_ID's is deficient in that a setuid root program | |
763 | * like sendmail, for example, cannot set its uid to be a normal | |
764 | * user and then switch back, because if you're root, setuid() sets | |
765 | * the saved uid too. If you don't like this, blame the bright people | |
766 | * in the POSIX committee and/or USG. Note that the BSD-style setreuid() | |
767 | * will allow a root program to temporarily drop privileges and be able to | |
768 | * regain them by swapping the real and effective uid. | |
769 | */ | |
ae1251ab | 770 | SYSCALL_DEFINE1(setuid, uid_t, uid) |
1da177e4 | 771 | { |
a29c33f4 | 772 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
773 | const struct cred *old; |
774 | struct cred *new; | |
1da177e4 | 775 | int retval; |
a29c33f4 EB |
776 | kuid_t kuid; |
777 | ||
778 | kuid = make_kuid(ns, uid); | |
779 | if (!uid_valid(kuid)) | |
780 | return -EINVAL; | |
1da177e4 | 781 | |
d84f4f99 DH |
782 | new = prepare_creds(); |
783 | if (!new) | |
784 | return -ENOMEM; | |
785 | old = current_cred(); | |
786 | ||
d84f4f99 | 787 | retval = -EPERM; |
fc832ad3 | 788 | if (nsown_capable(CAP_SETUID)) { |
a29c33f4 EB |
789 | new->suid = new->uid = kuid; |
790 | if (!uid_eq(kuid, old->uid)) { | |
54e99124 DG |
791 | retval = set_user(new); |
792 | if (retval < 0) | |
793 | goto error; | |
d84f4f99 | 794 | } |
a29c33f4 | 795 | } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) { |
d84f4f99 | 796 | goto error; |
1da177e4 | 797 | } |
1da177e4 | 798 | |
a29c33f4 | 799 | new->fsuid = new->euid = kuid; |
d84f4f99 DH |
800 | |
801 | retval = security_task_fix_setuid(new, old, LSM_SETID_ID); | |
802 | if (retval < 0) | |
803 | goto error; | |
1da177e4 | 804 | |
d84f4f99 | 805 | return commit_creds(new); |
1da177e4 | 806 | |
d84f4f99 DH |
807 | error: |
808 | abort_creds(new); | |
809 | return retval; | |
1da177e4 LT |
810 | } |
811 | ||
812 | ||
813 | /* | |
814 | * This function implements a generic ability to update ruid, euid, | |
815 | * and suid. This allows you to implement the 4.4 compatible seteuid(). | |
816 | */ | |
ae1251ab | 817 | SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) |
1da177e4 | 818 | { |
a29c33f4 | 819 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
820 | const struct cred *old; |
821 | struct cred *new; | |
1da177e4 | 822 | int retval; |
a29c33f4 EB |
823 | kuid_t kruid, keuid, ksuid; |
824 | ||
825 | kruid = make_kuid(ns, ruid); | |
826 | keuid = make_kuid(ns, euid); | |
827 | ksuid = make_kuid(ns, suid); | |
828 | ||
829 | if ((ruid != (uid_t) -1) && !uid_valid(kruid)) | |
830 | return -EINVAL; | |
831 | ||
832 | if ((euid != (uid_t) -1) && !uid_valid(keuid)) | |
833 | return -EINVAL; | |
834 | ||
835 | if ((suid != (uid_t) -1) && !uid_valid(ksuid)) | |
836 | return -EINVAL; | |
1da177e4 | 837 | |
d84f4f99 DH |
838 | new = prepare_creds(); |
839 | if (!new) | |
840 | return -ENOMEM; | |
841 | ||
d84f4f99 | 842 | old = current_cred(); |
1da177e4 | 843 | |
d84f4f99 | 844 | retval = -EPERM; |
fc832ad3 | 845 | if (!nsown_capable(CAP_SETUID)) { |
a29c33f4 EB |
846 | if (ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) && |
847 | !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid)) | |
d84f4f99 | 848 | goto error; |
a29c33f4 EB |
849 | if (euid != (uid_t) -1 && !uid_eq(keuid, old->uid) && |
850 | !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid)) | |
d84f4f99 | 851 | goto error; |
a29c33f4 EB |
852 | if (suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) && |
853 | !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid)) | |
d84f4f99 | 854 | goto error; |
1da177e4 | 855 | } |
d84f4f99 | 856 | |
1da177e4 | 857 | if (ruid != (uid_t) -1) { |
a29c33f4 EB |
858 | new->uid = kruid; |
859 | if (!uid_eq(kruid, old->uid)) { | |
54e99124 DG |
860 | retval = set_user(new); |
861 | if (retval < 0) | |
862 | goto error; | |
863 | } | |
1da177e4 | 864 | } |
d84f4f99 | 865 | if (euid != (uid_t) -1) |
a29c33f4 | 866 | new->euid = keuid; |
1da177e4 | 867 | if (suid != (uid_t) -1) |
a29c33f4 | 868 | new->suid = ksuid; |
d84f4f99 | 869 | new->fsuid = new->euid; |
1da177e4 | 870 | |
d84f4f99 DH |
871 | retval = security_task_fix_setuid(new, old, LSM_SETID_RES); |
872 | if (retval < 0) | |
873 | goto error; | |
1da177e4 | 874 | |
d84f4f99 | 875 | return commit_creds(new); |
1da177e4 | 876 | |
d84f4f99 DH |
877 | error: |
878 | abort_creds(new); | |
879 | return retval; | |
1da177e4 LT |
880 | } |
881 | ||
a29c33f4 | 882 | SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp) |
1da177e4 | 883 | { |
86a264ab | 884 | const struct cred *cred = current_cred(); |
1da177e4 | 885 | int retval; |
a29c33f4 EB |
886 | uid_t ruid, euid, suid; |
887 | ||
888 | ruid = from_kuid_munged(cred->user_ns, cred->uid); | |
889 | euid = from_kuid_munged(cred->user_ns, cred->euid); | |
890 | suid = from_kuid_munged(cred->user_ns, cred->suid); | |
1da177e4 | 891 | |
a29c33f4 EB |
892 | if (!(retval = put_user(ruid, ruidp)) && |
893 | !(retval = put_user(euid, euidp))) | |
894 | retval = put_user(suid, suidp); | |
1da177e4 LT |
895 | |
896 | return retval; | |
897 | } | |
898 | ||
899 | /* | |
900 | * Same as above, but for rgid, egid, sgid. | |
901 | */ | |
ae1251ab | 902 | SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) |
1da177e4 | 903 | { |
a29c33f4 | 904 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
905 | const struct cred *old; |
906 | struct cred *new; | |
1da177e4 | 907 | int retval; |
a29c33f4 EB |
908 | kgid_t krgid, kegid, ksgid; |
909 | ||
910 | krgid = make_kgid(ns, rgid); | |
911 | kegid = make_kgid(ns, egid); | |
912 | ksgid = make_kgid(ns, sgid); | |
913 | ||
914 | if ((rgid != (gid_t) -1) && !gid_valid(krgid)) | |
915 | return -EINVAL; | |
916 | if ((egid != (gid_t) -1) && !gid_valid(kegid)) | |
917 | return -EINVAL; | |
918 | if ((sgid != (gid_t) -1) && !gid_valid(ksgid)) | |
919 | return -EINVAL; | |
1da177e4 | 920 | |
d84f4f99 DH |
921 | new = prepare_creds(); |
922 | if (!new) | |
923 | return -ENOMEM; | |
924 | old = current_cred(); | |
925 | ||
d84f4f99 | 926 | retval = -EPERM; |
fc832ad3 | 927 | if (!nsown_capable(CAP_SETGID)) { |
a29c33f4 EB |
928 | if (rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) && |
929 | !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid)) | |
d84f4f99 | 930 | goto error; |
a29c33f4 EB |
931 | if (egid != (gid_t) -1 && !gid_eq(kegid, old->gid) && |
932 | !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid)) | |
d84f4f99 | 933 | goto error; |
a29c33f4 EB |
934 | if (sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) && |
935 | !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid)) | |
d84f4f99 | 936 | goto error; |
1da177e4 | 937 | } |
d84f4f99 | 938 | |
1da177e4 | 939 | if (rgid != (gid_t) -1) |
a29c33f4 | 940 | new->gid = krgid; |
d84f4f99 | 941 | if (egid != (gid_t) -1) |
a29c33f4 | 942 | new->egid = kegid; |
1da177e4 | 943 | if (sgid != (gid_t) -1) |
a29c33f4 | 944 | new->sgid = ksgid; |
d84f4f99 | 945 | new->fsgid = new->egid; |
1da177e4 | 946 | |
d84f4f99 DH |
947 | return commit_creds(new); |
948 | ||
949 | error: | |
950 | abort_creds(new); | |
951 | return retval; | |
1da177e4 LT |
952 | } |
953 | ||
a29c33f4 | 954 | SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp) |
1da177e4 | 955 | { |
86a264ab | 956 | const struct cred *cred = current_cred(); |
1da177e4 | 957 | int retval; |
a29c33f4 EB |
958 | gid_t rgid, egid, sgid; |
959 | ||
960 | rgid = from_kgid_munged(cred->user_ns, cred->gid); | |
961 | egid = from_kgid_munged(cred->user_ns, cred->egid); | |
962 | sgid = from_kgid_munged(cred->user_ns, cred->sgid); | |
1da177e4 | 963 | |
a29c33f4 EB |
964 | if (!(retval = put_user(rgid, rgidp)) && |
965 | !(retval = put_user(egid, egidp))) | |
966 | retval = put_user(sgid, sgidp); | |
1da177e4 LT |
967 | |
968 | return retval; | |
969 | } | |
970 | ||
971 | ||
972 | /* | |
973 | * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This | |
974 | * is used for "access()" and for the NFS daemon (letting nfsd stay at | |
975 | * whatever uid it wants to). It normally shadows "euid", except when | |
976 | * explicitly set by setfsuid() or for access.. | |
977 | */ | |
ae1251ab | 978 | SYSCALL_DEFINE1(setfsuid, uid_t, uid) |
1da177e4 | 979 | { |
d84f4f99 DH |
980 | const struct cred *old; |
981 | struct cred *new; | |
982 | uid_t old_fsuid; | |
a29c33f4 EB |
983 | kuid_t kuid; |
984 | ||
985 | old = current_cred(); | |
986 | old_fsuid = from_kuid_munged(old->user_ns, old->fsuid); | |
987 | ||
988 | kuid = make_kuid(old->user_ns, uid); | |
989 | if (!uid_valid(kuid)) | |
990 | return old_fsuid; | |
1da177e4 | 991 | |
d84f4f99 DH |
992 | new = prepare_creds(); |
993 | if (!new) | |
a29c33f4 | 994 | return old_fsuid; |
1da177e4 | 995 | |
a29c33f4 EB |
996 | if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) || |
997 | uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) || | |
fc832ad3 | 998 | nsown_capable(CAP_SETUID)) { |
a29c33f4 EB |
999 | if (!uid_eq(kuid, old->fsuid)) { |
1000 | new->fsuid = kuid; | |
d84f4f99 DH |
1001 | if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) |
1002 | goto change_okay; | |
1da177e4 | 1003 | } |
1da177e4 LT |
1004 | } |
1005 | ||
d84f4f99 DH |
1006 | abort_creds(new); |
1007 | return old_fsuid; | |
1da177e4 | 1008 | |
d84f4f99 DH |
1009 | change_okay: |
1010 | commit_creds(new); | |
1da177e4 LT |
1011 | return old_fsuid; |
1012 | } | |
1013 | ||
1014 | /* | |
f42df9e6 | 1015 | * Samma på svenska.. |
1da177e4 | 1016 | */ |
ae1251ab | 1017 | SYSCALL_DEFINE1(setfsgid, gid_t, gid) |
1da177e4 | 1018 | { |
d84f4f99 DH |
1019 | const struct cred *old; |
1020 | struct cred *new; | |
1021 | gid_t old_fsgid; | |
a29c33f4 EB |
1022 | kgid_t kgid; |
1023 | ||
1024 | old = current_cred(); | |
1025 | old_fsgid = from_kgid_munged(old->user_ns, old->fsgid); | |
1026 | ||
1027 | kgid = make_kgid(old->user_ns, gid); | |
1028 | if (!gid_valid(kgid)) | |
1029 | return old_fsgid; | |
d84f4f99 DH |
1030 | |
1031 | new = prepare_creds(); | |
1032 | if (!new) | |
a29c33f4 | 1033 | return old_fsgid; |
1da177e4 | 1034 | |
a29c33f4 EB |
1035 | if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) || |
1036 | gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) || | |
fc832ad3 | 1037 | nsown_capable(CAP_SETGID)) { |
a29c33f4 EB |
1038 | if (!gid_eq(kgid, old->fsgid)) { |
1039 | new->fsgid = kgid; | |
d84f4f99 | 1040 | goto change_okay; |
1da177e4 | 1041 | } |
1da177e4 | 1042 | } |
d84f4f99 | 1043 | |
d84f4f99 DH |
1044 | abort_creds(new); |
1045 | return old_fsgid; | |
1046 | ||
1047 | change_okay: | |
1048 | commit_creds(new); | |
1da177e4 LT |
1049 | return old_fsgid; |
1050 | } | |
1051 | ||
4a22f166 SR |
1052 | /** |
1053 | * sys_getpid - return the thread group id of the current process | |
1054 | * | |
1055 | * Note, despite the name, this returns the tgid not the pid. The tgid and | |
1056 | * the pid are identical unless CLONE_THREAD was specified on clone() in | |
1057 | * which case the tgid is the same in all threads of the same group. | |
1058 | * | |
1059 | * This is SMP safe as current->tgid does not change. | |
1060 | */ | |
1061 | SYSCALL_DEFINE0(getpid) | |
1062 | { | |
1063 | return task_tgid_vnr(current); | |
1064 | } | |
1065 | ||
1066 | /* Thread ID - the internal kernel "pid" */ | |
1067 | SYSCALL_DEFINE0(gettid) | |
1068 | { | |
1069 | return task_pid_vnr(current); | |
1070 | } | |
1071 | ||
1072 | /* | |
1073 | * Accessing ->real_parent is not SMP-safe, it could | |
1074 | * change from under us. However, we can use a stale | |
1075 | * value of ->real_parent under rcu_read_lock(), see | |
1076 | * release_task()->call_rcu(delayed_put_task_struct). | |
1077 | */ | |
1078 | SYSCALL_DEFINE0(getppid) | |
1079 | { | |
1080 | int pid; | |
1081 | ||
1082 | rcu_read_lock(); | |
1083 | pid = task_tgid_vnr(rcu_dereference(current->real_parent)); | |
1084 | rcu_read_unlock(); | |
1085 | ||
1086 | return pid; | |
1087 | } | |
1088 | ||
1089 | SYSCALL_DEFINE0(getuid) | |
1090 | { | |
1091 | /* Only we change this so SMP safe */ | |
1092 | return from_kuid_munged(current_user_ns(), current_uid()); | |
1093 | } | |
1094 | ||
1095 | SYSCALL_DEFINE0(geteuid) | |
1096 | { | |
1097 | /* Only we change this so SMP safe */ | |
1098 | return from_kuid_munged(current_user_ns(), current_euid()); | |
1099 | } | |
1100 | ||
1101 | SYSCALL_DEFINE0(getgid) | |
1102 | { | |
1103 | /* Only we change this so SMP safe */ | |
1104 | return from_kgid_munged(current_user_ns(), current_gid()); | |
1105 | } | |
1106 | ||
1107 | SYSCALL_DEFINE0(getegid) | |
1108 | { | |
1109 | /* Only we change this so SMP safe */ | |
1110 | return from_kgid_munged(current_user_ns(), current_egid()); | |
1111 | } | |
1112 | ||
f06febc9 FM |
1113 | void do_sys_times(struct tms *tms) |
1114 | { | |
0cf55e1e | 1115 | cputime_t tgutime, tgstime, cutime, cstime; |
f06febc9 | 1116 | |
2b5fe6de | 1117 | spin_lock_irq(¤t->sighand->siglock); |
e80d0a1a | 1118 | thread_group_cputime_adjusted(current, &tgutime, &tgstime); |
f06febc9 FM |
1119 | cutime = current->signal->cutime; |
1120 | cstime = current->signal->cstime; | |
1121 | spin_unlock_irq(¤t->sighand->siglock); | |
0cf55e1e HS |
1122 | tms->tms_utime = cputime_to_clock_t(tgutime); |
1123 | tms->tms_stime = cputime_to_clock_t(tgstime); | |
f06febc9 FM |
1124 | tms->tms_cutime = cputime_to_clock_t(cutime); |
1125 | tms->tms_cstime = cputime_to_clock_t(cstime); | |
1126 | } | |
1127 | ||
58fd3aa2 | 1128 | SYSCALL_DEFINE1(times, struct tms __user *, tbuf) |
1da177e4 | 1129 | { |
1da177e4 LT |
1130 | if (tbuf) { |
1131 | struct tms tmp; | |
f06febc9 FM |
1132 | |
1133 | do_sys_times(&tmp); | |
1da177e4 LT |
1134 | if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
1135 | return -EFAULT; | |
1136 | } | |
e3d5a27d | 1137 | force_successful_syscall_return(); |
1da177e4 LT |
1138 | return (long) jiffies_64_to_clock_t(get_jiffies_64()); |
1139 | } | |
1140 | ||
1141 | /* | |
1142 | * This needs some heavy checking ... | |
1143 | * I just haven't the stomach for it. I also don't fully | |
1144 | * understand sessions/pgrp etc. Let somebody who does explain it. | |
1145 | * | |
1146 | * OK, I think I have the protection semantics right.... this is really | |
1147 | * only important on a multi-user system anyway, to make sure one user | |
1148 | * can't send a signal to a process owned by another. -TYT, 12/12/91 | |
1149 | * | |
1150 | * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. | |
1151 | * LBT 04.03.94 | |
1152 | */ | |
b290ebe2 | 1153 | SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) |
1da177e4 LT |
1154 | { |
1155 | struct task_struct *p; | |
ee0acf90 | 1156 | struct task_struct *group_leader = current->group_leader; |
4e021306 ON |
1157 | struct pid *pgrp; |
1158 | int err; | |
1da177e4 LT |
1159 | |
1160 | if (!pid) | |
b488893a | 1161 | pid = task_pid_vnr(group_leader); |
1da177e4 LT |
1162 | if (!pgid) |
1163 | pgid = pid; | |
1164 | if (pgid < 0) | |
1165 | return -EINVAL; | |
950eaaca | 1166 | rcu_read_lock(); |
1da177e4 LT |
1167 | |
1168 | /* From this point forward we keep holding onto the tasklist lock | |
1169 | * so that our parent does not change from under us. -DaveM | |
1170 | */ | |
1171 | write_lock_irq(&tasklist_lock); | |
1172 | ||
1173 | err = -ESRCH; | |
4e021306 | 1174 | p = find_task_by_vpid(pid); |
1da177e4 LT |
1175 | if (!p) |
1176 | goto out; | |
1177 | ||
1178 | err = -EINVAL; | |
1179 | if (!thread_group_leader(p)) | |
1180 | goto out; | |
1181 | ||
4e021306 | 1182 | if (same_thread_group(p->real_parent, group_leader)) { |
1da177e4 | 1183 | err = -EPERM; |
41487c65 | 1184 | if (task_session(p) != task_session(group_leader)) |
1da177e4 LT |
1185 | goto out; |
1186 | err = -EACCES; | |
1187 | if (p->did_exec) | |
1188 | goto out; | |
1189 | } else { | |
1190 | err = -ESRCH; | |
ee0acf90 | 1191 | if (p != group_leader) |
1da177e4 LT |
1192 | goto out; |
1193 | } | |
1194 | ||
1195 | err = -EPERM; | |
1196 | if (p->signal->leader) | |
1197 | goto out; | |
1198 | ||
4e021306 | 1199 | pgrp = task_pid(p); |
1da177e4 | 1200 | if (pgid != pid) { |
b488893a | 1201 | struct task_struct *g; |
1da177e4 | 1202 | |
4e021306 ON |
1203 | pgrp = find_vpid(pgid); |
1204 | g = pid_task(pgrp, PIDTYPE_PGID); | |
41487c65 | 1205 | if (!g || task_session(g) != task_session(group_leader)) |
f020bc46 | 1206 | goto out; |
1da177e4 LT |
1207 | } |
1208 | ||
1da177e4 LT |
1209 | err = security_task_setpgid(p, pgid); |
1210 | if (err) | |
1211 | goto out; | |
1212 | ||
1b0f7ffd | 1213 | if (task_pgrp(p) != pgrp) |
83beaf3c | 1214 | change_pid(p, PIDTYPE_PGID, pgrp); |
1da177e4 LT |
1215 | |
1216 | err = 0; | |
1217 | out: | |
1218 | /* All paths lead to here, thus we are safe. -DaveM */ | |
1219 | write_unlock_irq(&tasklist_lock); | |
950eaaca | 1220 | rcu_read_unlock(); |
1da177e4 LT |
1221 | return err; |
1222 | } | |
1223 | ||
dbf040d9 | 1224 | SYSCALL_DEFINE1(getpgid, pid_t, pid) |
1da177e4 | 1225 | { |
12a3de0a ON |
1226 | struct task_struct *p; |
1227 | struct pid *grp; | |
1228 | int retval; | |
1229 | ||
1230 | rcu_read_lock(); | |
756184b7 | 1231 | if (!pid) |
12a3de0a | 1232 | grp = task_pgrp(current); |
756184b7 | 1233 | else { |
1da177e4 | 1234 | retval = -ESRCH; |
12a3de0a ON |
1235 | p = find_task_by_vpid(pid); |
1236 | if (!p) | |
1237 | goto out; | |
1238 | grp = task_pgrp(p); | |
1239 | if (!grp) | |
1240 | goto out; | |
1241 | ||
1242 | retval = security_task_getpgid(p); | |
1243 | if (retval) | |
1244 | goto out; | |
1da177e4 | 1245 | } |
12a3de0a ON |
1246 | retval = pid_vnr(grp); |
1247 | out: | |
1248 | rcu_read_unlock(); | |
1249 | return retval; | |
1da177e4 LT |
1250 | } |
1251 | ||
1252 | #ifdef __ARCH_WANT_SYS_GETPGRP | |
1253 | ||
dbf040d9 | 1254 | SYSCALL_DEFINE0(getpgrp) |
1da177e4 | 1255 | { |
12a3de0a | 1256 | return sys_getpgid(0); |
1da177e4 LT |
1257 | } |
1258 | ||
1259 | #endif | |
1260 | ||
dbf040d9 | 1261 | SYSCALL_DEFINE1(getsid, pid_t, pid) |
1da177e4 | 1262 | { |
1dd768c0 ON |
1263 | struct task_struct *p; |
1264 | struct pid *sid; | |
1265 | int retval; | |
1266 | ||
1267 | rcu_read_lock(); | |
756184b7 | 1268 | if (!pid) |
1dd768c0 | 1269 | sid = task_session(current); |
756184b7 | 1270 | else { |
1da177e4 | 1271 | retval = -ESRCH; |
1dd768c0 ON |
1272 | p = find_task_by_vpid(pid); |
1273 | if (!p) | |
1274 | goto out; | |
1275 | sid = task_session(p); | |
1276 | if (!sid) | |
1277 | goto out; | |
1278 | ||
1279 | retval = security_task_getsid(p); | |
1280 | if (retval) | |
1281 | goto out; | |
1da177e4 | 1282 | } |
1dd768c0 ON |
1283 | retval = pid_vnr(sid); |
1284 | out: | |
1285 | rcu_read_unlock(); | |
1286 | return retval; | |
1da177e4 LT |
1287 | } |
1288 | ||
b290ebe2 | 1289 | SYSCALL_DEFINE0(setsid) |
1da177e4 | 1290 | { |
e19f247a | 1291 | struct task_struct *group_leader = current->group_leader; |
e4cc0a9c ON |
1292 | struct pid *sid = task_pid(group_leader); |
1293 | pid_t session = pid_vnr(sid); | |
1da177e4 LT |
1294 | int err = -EPERM; |
1295 | ||
1da177e4 | 1296 | write_lock_irq(&tasklist_lock); |
390e2ff0 EB |
1297 | /* Fail if I am already a session leader */ |
1298 | if (group_leader->signal->leader) | |
1299 | goto out; | |
1300 | ||
430c6231 ON |
1301 | /* Fail if a process group id already exists that equals the |
1302 | * proposed session id. | |
390e2ff0 | 1303 | */ |
6806aac6 | 1304 | if (pid_task(sid, PIDTYPE_PGID)) |
1da177e4 LT |
1305 | goto out; |
1306 | ||
e19f247a | 1307 | group_leader->signal->leader = 1; |
8520d7c7 | 1308 | __set_special_pids(sid); |
24ec839c | 1309 | |
9c9f4ded | 1310 | proc_clear_tty(group_leader); |
24ec839c | 1311 | |
e4cc0a9c | 1312 | err = session; |
1da177e4 LT |
1313 | out: |
1314 | write_unlock_irq(&tasklist_lock); | |
5091faa4 | 1315 | if (err > 0) { |
0d0df599 | 1316 | proc_sid_connector(group_leader); |
5091faa4 MG |
1317 | sched_autogroup_create_attach(group_leader); |
1318 | } | |
1da177e4 LT |
1319 | return err; |
1320 | } | |
1321 | ||
1da177e4 LT |
1322 | DECLARE_RWSEM(uts_sem); |
1323 | ||
e28cbf22 CH |
1324 | #ifdef COMPAT_UTS_MACHINE |
1325 | #define override_architecture(name) \ | |
46da2766 | 1326 | (personality(current->personality) == PER_LINUX32 && \ |
e28cbf22 CH |
1327 | copy_to_user(name->machine, COMPAT_UTS_MACHINE, \ |
1328 | sizeof(COMPAT_UTS_MACHINE))) | |
1329 | #else | |
1330 | #define override_architecture(name) 0 | |
1331 | #endif | |
1332 | ||
be27425d AK |
1333 | /* |
1334 | * Work around broken programs that cannot handle "Linux 3.0". | |
1335 | * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40 | |
1336 | */ | |
2702b152 | 1337 | static int override_release(char __user *release, size_t len) |
be27425d AK |
1338 | { |
1339 | int ret = 0; | |
be27425d AK |
1340 | |
1341 | if (current->personality & UNAME26) { | |
2702b152 KC |
1342 | const char *rest = UTS_RELEASE; |
1343 | char buf[65] = { 0 }; | |
be27425d AK |
1344 | int ndots = 0; |
1345 | unsigned v; | |
2702b152 | 1346 | size_t copy; |
be27425d AK |
1347 | |
1348 | while (*rest) { | |
1349 | if (*rest == '.' && ++ndots >= 3) | |
1350 | break; | |
1351 | if (!isdigit(*rest) && *rest != '.') | |
1352 | break; | |
1353 | rest++; | |
1354 | } | |
1355 | v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 40; | |
31fd84b9 | 1356 | copy = clamp_t(size_t, len, 1, sizeof(buf)); |
2702b152 KC |
1357 | copy = scnprintf(buf, copy, "2.6.%u%s", v, rest); |
1358 | ret = copy_to_user(release, buf, copy + 1); | |
be27425d AK |
1359 | } |
1360 | return ret; | |
1361 | } | |
1362 | ||
e48fbb69 | 1363 | SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name) |
1da177e4 LT |
1364 | { |
1365 | int errno = 0; | |
1366 | ||
1367 | down_read(&uts_sem); | |
e9ff3990 | 1368 | if (copy_to_user(name, utsname(), sizeof *name)) |
1da177e4 LT |
1369 | errno = -EFAULT; |
1370 | up_read(&uts_sem); | |
e28cbf22 | 1371 | |
be27425d AK |
1372 | if (!errno && override_release(name->release, sizeof(name->release))) |
1373 | errno = -EFAULT; | |
e28cbf22 CH |
1374 | if (!errno && override_architecture(name)) |
1375 | errno = -EFAULT; | |
1da177e4 LT |
1376 | return errno; |
1377 | } | |
1378 | ||
5cacdb4a CH |
1379 | #ifdef __ARCH_WANT_SYS_OLD_UNAME |
1380 | /* | |
1381 | * Old cruft | |
1382 | */ | |
1383 | SYSCALL_DEFINE1(uname, struct old_utsname __user *, name) | |
1384 | { | |
1385 | int error = 0; | |
1386 | ||
1387 | if (!name) | |
1388 | return -EFAULT; | |
1389 | ||
1390 | down_read(&uts_sem); | |
1391 | if (copy_to_user(name, utsname(), sizeof(*name))) | |
1392 | error = -EFAULT; | |
1393 | up_read(&uts_sem); | |
1394 | ||
be27425d AK |
1395 | if (!error && override_release(name->release, sizeof(name->release))) |
1396 | error = -EFAULT; | |
5cacdb4a CH |
1397 | if (!error && override_architecture(name)) |
1398 | error = -EFAULT; | |
1399 | return error; | |
1400 | } | |
1401 | ||
1402 | SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name) | |
1403 | { | |
1404 | int error; | |
1405 | ||
1406 | if (!name) | |
1407 | return -EFAULT; | |
1408 | if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname))) | |
1409 | return -EFAULT; | |
1410 | ||
1411 | down_read(&uts_sem); | |
1412 | error = __copy_to_user(&name->sysname, &utsname()->sysname, | |
1413 | __OLD_UTS_LEN); | |
1414 | error |= __put_user(0, name->sysname + __OLD_UTS_LEN); | |
1415 | error |= __copy_to_user(&name->nodename, &utsname()->nodename, | |
1416 | __OLD_UTS_LEN); | |
1417 | error |= __put_user(0, name->nodename + __OLD_UTS_LEN); | |
1418 | error |= __copy_to_user(&name->release, &utsname()->release, | |
1419 | __OLD_UTS_LEN); | |
1420 | error |= __put_user(0, name->release + __OLD_UTS_LEN); | |
1421 | error |= __copy_to_user(&name->version, &utsname()->version, | |
1422 | __OLD_UTS_LEN); | |
1423 | error |= __put_user(0, name->version + __OLD_UTS_LEN); | |
1424 | error |= __copy_to_user(&name->machine, &utsname()->machine, | |
1425 | __OLD_UTS_LEN); | |
1426 | error |= __put_user(0, name->machine + __OLD_UTS_LEN); | |
1427 | up_read(&uts_sem); | |
1428 | ||
1429 | if (!error && override_architecture(name)) | |
1430 | error = -EFAULT; | |
be27425d AK |
1431 | if (!error && override_release(name->release, sizeof(name->release))) |
1432 | error = -EFAULT; | |
5cacdb4a CH |
1433 | return error ? -EFAULT : 0; |
1434 | } | |
1435 | #endif | |
1436 | ||
5a8a82b1 | 1437 | SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) |
1da177e4 LT |
1438 | { |
1439 | int errno; | |
1440 | char tmp[__NEW_UTS_LEN]; | |
1441 | ||
bb96a6f5 | 1442 | if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
1da177e4 | 1443 | return -EPERM; |
fc832ad3 | 1444 | |
1da177e4 LT |
1445 | if (len < 0 || len > __NEW_UTS_LEN) |
1446 | return -EINVAL; | |
1447 | down_write(&uts_sem); | |
1448 | errno = -EFAULT; | |
1449 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1450 | struct new_utsname *u = utsname(); |
1451 | ||
1452 | memcpy(u->nodename, tmp, len); | |
1453 | memset(u->nodename + len, 0, sizeof(u->nodename) - len); | |
1da177e4 | 1454 | errno = 0; |
499eea6b | 1455 | uts_proc_notify(UTS_PROC_HOSTNAME); |
1da177e4 LT |
1456 | } |
1457 | up_write(&uts_sem); | |
1458 | return errno; | |
1459 | } | |
1460 | ||
1461 | #ifdef __ARCH_WANT_SYS_GETHOSTNAME | |
1462 | ||
5a8a82b1 | 1463 | SYSCALL_DEFINE2(gethostname, char __user *, name, int, len) |
1da177e4 LT |
1464 | { |
1465 | int i, errno; | |
9679e4dd | 1466 | struct new_utsname *u; |
1da177e4 LT |
1467 | |
1468 | if (len < 0) | |
1469 | return -EINVAL; | |
1470 | down_read(&uts_sem); | |
9679e4dd AM |
1471 | u = utsname(); |
1472 | i = 1 + strlen(u->nodename); | |
1da177e4 LT |
1473 | if (i > len) |
1474 | i = len; | |
1475 | errno = 0; | |
9679e4dd | 1476 | if (copy_to_user(name, u->nodename, i)) |
1da177e4 LT |
1477 | errno = -EFAULT; |
1478 | up_read(&uts_sem); | |
1479 | return errno; | |
1480 | } | |
1481 | ||
1482 | #endif | |
1483 | ||
1484 | /* | |
1485 | * Only setdomainname; getdomainname can be implemented by calling | |
1486 | * uname() | |
1487 | */ | |
5a8a82b1 | 1488 | SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) |
1da177e4 LT |
1489 | { |
1490 | int errno; | |
1491 | char tmp[__NEW_UTS_LEN]; | |
1492 | ||
fc832ad3 | 1493 | if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
1da177e4 LT |
1494 | return -EPERM; |
1495 | if (len < 0 || len > __NEW_UTS_LEN) | |
1496 | return -EINVAL; | |
1497 | ||
1498 | down_write(&uts_sem); | |
1499 | errno = -EFAULT; | |
1500 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1501 | struct new_utsname *u = utsname(); |
1502 | ||
1503 | memcpy(u->domainname, tmp, len); | |
1504 | memset(u->domainname + len, 0, sizeof(u->domainname) - len); | |
1da177e4 | 1505 | errno = 0; |
499eea6b | 1506 | uts_proc_notify(UTS_PROC_DOMAINNAME); |
1da177e4 LT |
1507 | } |
1508 | up_write(&uts_sem); | |
1509 | return errno; | |
1510 | } | |
1511 | ||
e48fbb69 | 1512 | SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1da177e4 | 1513 | { |
b9518345 JS |
1514 | struct rlimit value; |
1515 | int ret; | |
1516 | ||
1517 | ret = do_prlimit(current, resource, NULL, &value); | |
1518 | if (!ret) | |
1519 | ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; | |
1520 | ||
1521 | return ret; | |
1da177e4 LT |
1522 | } |
1523 | ||
1524 | #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT | |
1525 | ||
1526 | /* | |
1527 | * Back compatibility for getrlimit. Needed for some apps. | |
1528 | */ | |
1529 | ||
e48fbb69 HC |
1530 | SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, |
1531 | struct rlimit __user *, rlim) | |
1da177e4 LT |
1532 | { |
1533 | struct rlimit x; | |
1534 | if (resource >= RLIM_NLIMITS) | |
1535 | return -EINVAL; | |
1536 | ||
1537 | task_lock(current->group_leader); | |
1538 | x = current->signal->rlim[resource]; | |
1539 | task_unlock(current->group_leader); | |
756184b7 | 1540 | if (x.rlim_cur > 0x7FFFFFFF) |
1da177e4 | 1541 | x.rlim_cur = 0x7FFFFFFF; |
756184b7 | 1542 | if (x.rlim_max > 0x7FFFFFFF) |
1da177e4 LT |
1543 | x.rlim_max = 0x7FFFFFFF; |
1544 | return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0; | |
1545 | } | |
1546 | ||
1547 | #endif | |
1548 | ||
c022a0ac JS |
1549 | static inline bool rlim64_is_infinity(__u64 rlim64) |
1550 | { | |
1551 | #if BITS_PER_LONG < 64 | |
1552 | return rlim64 >= ULONG_MAX; | |
1553 | #else | |
1554 | return rlim64 == RLIM64_INFINITY; | |
1555 | #endif | |
1556 | } | |
1557 | ||
1558 | static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64) | |
1559 | { | |
1560 | if (rlim->rlim_cur == RLIM_INFINITY) | |
1561 | rlim64->rlim_cur = RLIM64_INFINITY; | |
1562 | else | |
1563 | rlim64->rlim_cur = rlim->rlim_cur; | |
1564 | if (rlim->rlim_max == RLIM_INFINITY) | |
1565 | rlim64->rlim_max = RLIM64_INFINITY; | |
1566 | else | |
1567 | rlim64->rlim_max = rlim->rlim_max; | |
1568 | } | |
1569 | ||
1570 | static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim) | |
1571 | { | |
1572 | if (rlim64_is_infinity(rlim64->rlim_cur)) | |
1573 | rlim->rlim_cur = RLIM_INFINITY; | |
1574 | else | |
1575 | rlim->rlim_cur = (unsigned long)rlim64->rlim_cur; | |
1576 | if (rlim64_is_infinity(rlim64->rlim_max)) | |
1577 | rlim->rlim_max = RLIM_INFINITY; | |
1578 | else | |
1579 | rlim->rlim_max = (unsigned long)rlim64->rlim_max; | |
1580 | } | |
1581 | ||
1c1e618d | 1582 | /* make sure you are allowed to change @tsk limits before calling this */ |
5b41535a JS |
1583 | int do_prlimit(struct task_struct *tsk, unsigned int resource, |
1584 | struct rlimit *new_rlim, struct rlimit *old_rlim) | |
1da177e4 | 1585 | { |
5b41535a | 1586 | struct rlimit *rlim; |
86f162f4 | 1587 | int retval = 0; |
1da177e4 LT |
1588 | |
1589 | if (resource >= RLIM_NLIMITS) | |
1590 | return -EINVAL; | |
5b41535a JS |
1591 | if (new_rlim) { |
1592 | if (new_rlim->rlim_cur > new_rlim->rlim_max) | |
1593 | return -EINVAL; | |
1594 | if (resource == RLIMIT_NOFILE && | |
1595 | new_rlim->rlim_max > sysctl_nr_open) | |
1596 | return -EPERM; | |
1597 | } | |
1da177e4 | 1598 | |
1c1e618d JS |
1599 | /* protect tsk->signal and tsk->sighand from disappearing */ |
1600 | read_lock(&tasklist_lock); | |
1601 | if (!tsk->sighand) { | |
1602 | retval = -ESRCH; | |
1603 | goto out; | |
1604 | } | |
1605 | ||
5b41535a | 1606 | rlim = tsk->signal->rlim + resource; |
86f162f4 | 1607 | task_lock(tsk->group_leader); |
5b41535a | 1608 | if (new_rlim) { |
fc832ad3 SH |
1609 | /* Keep the capable check against init_user_ns until |
1610 | cgroups can contain all limits */ | |
5b41535a JS |
1611 | if (new_rlim->rlim_max > rlim->rlim_max && |
1612 | !capable(CAP_SYS_RESOURCE)) | |
1613 | retval = -EPERM; | |
1614 | if (!retval) | |
1615 | retval = security_task_setrlimit(tsk->group_leader, | |
1616 | resource, new_rlim); | |
1617 | if (resource == RLIMIT_CPU && new_rlim->rlim_cur == 0) { | |
1618 | /* | |
1619 | * The caller is asking for an immediate RLIMIT_CPU | |
1620 | * expiry. But we use the zero value to mean "it was | |
1621 | * never set". So let's cheat and make it one second | |
1622 | * instead | |
1623 | */ | |
1624 | new_rlim->rlim_cur = 1; | |
1625 | } | |
1626 | } | |
1627 | if (!retval) { | |
1628 | if (old_rlim) | |
1629 | *old_rlim = *rlim; | |
1630 | if (new_rlim) | |
1631 | *rlim = *new_rlim; | |
9926e4c7 | 1632 | } |
7855c35d | 1633 | task_unlock(tsk->group_leader); |
1da177e4 | 1634 | |
d3561f78 AM |
1635 | /* |
1636 | * RLIMIT_CPU handling. Note that the kernel fails to return an error | |
1637 | * code if it rejected the user's attempt to set RLIMIT_CPU. This is a | |
1638 | * very long-standing error, and fixing it now risks breakage of | |
1639 | * applications, so we live with it | |
1640 | */ | |
5b41535a JS |
1641 | if (!retval && new_rlim && resource == RLIMIT_CPU && |
1642 | new_rlim->rlim_cur != RLIM_INFINITY) | |
1643 | update_rlimit_cpu(tsk, new_rlim->rlim_cur); | |
ec9e16ba | 1644 | out: |
1c1e618d | 1645 | read_unlock(&tasklist_lock); |
2fb9d268 | 1646 | return retval; |
1da177e4 LT |
1647 | } |
1648 | ||
c022a0ac JS |
1649 | /* rcu lock must be held */ |
1650 | static int check_prlimit_permission(struct task_struct *task) | |
1651 | { | |
1652 | const struct cred *cred = current_cred(), *tcred; | |
1653 | ||
fc832ad3 SH |
1654 | if (current == task) |
1655 | return 0; | |
c022a0ac | 1656 | |
fc832ad3 | 1657 | tcred = __task_cred(task); |
5af66203 EB |
1658 | if (uid_eq(cred->uid, tcred->euid) && |
1659 | uid_eq(cred->uid, tcred->suid) && | |
1660 | uid_eq(cred->uid, tcred->uid) && | |
1661 | gid_eq(cred->gid, tcred->egid) && | |
1662 | gid_eq(cred->gid, tcred->sgid) && | |
1663 | gid_eq(cred->gid, tcred->gid)) | |
fc832ad3 | 1664 | return 0; |
c4a4d603 | 1665 | if (ns_capable(tcred->user_ns, CAP_SYS_RESOURCE)) |
fc832ad3 SH |
1666 | return 0; |
1667 | ||
1668 | return -EPERM; | |
c022a0ac JS |
1669 | } |
1670 | ||
1671 | SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource, | |
1672 | const struct rlimit64 __user *, new_rlim, | |
1673 | struct rlimit64 __user *, old_rlim) | |
1674 | { | |
1675 | struct rlimit64 old64, new64; | |
1676 | struct rlimit old, new; | |
1677 | struct task_struct *tsk; | |
1678 | int ret; | |
1679 | ||
1680 | if (new_rlim) { | |
1681 | if (copy_from_user(&new64, new_rlim, sizeof(new64))) | |
1682 | return -EFAULT; | |
1683 | rlim64_to_rlim(&new64, &new); | |
1684 | } | |
1685 | ||
1686 | rcu_read_lock(); | |
1687 | tsk = pid ? find_task_by_vpid(pid) : current; | |
1688 | if (!tsk) { | |
1689 | rcu_read_unlock(); | |
1690 | return -ESRCH; | |
1691 | } | |
1692 | ret = check_prlimit_permission(tsk); | |
1693 | if (ret) { | |
1694 | rcu_read_unlock(); | |
1695 | return ret; | |
1696 | } | |
1697 | get_task_struct(tsk); | |
1698 | rcu_read_unlock(); | |
1699 | ||
1700 | ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL, | |
1701 | old_rlim ? &old : NULL); | |
1702 | ||
1703 | if (!ret && old_rlim) { | |
1704 | rlim_to_rlim64(&old, &old64); | |
1705 | if (copy_to_user(old_rlim, &old64, sizeof(old64))) | |
1706 | ret = -EFAULT; | |
1707 | } | |
1708 | ||
1709 | put_task_struct(tsk); | |
1710 | return ret; | |
1711 | } | |
1712 | ||
7855c35d JS |
1713 | SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1714 | { | |
1715 | struct rlimit new_rlim; | |
1716 | ||
1717 | if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) | |
1718 | return -EFAULT; | |
5b41535a | 1719 | return do_prlimit(current, resource, &new_rlim, NULL); |
7855c35d JS |
1720 | } |
1721 | ||
1da177e4 LT |
1722 | /* |
1723 | * It would make sense to put struct rusage in the task_struct, | |
1724 | * except that would make the task_struct be *really big*. After | |
1725 | * task_struct gets moved into malloc'ed memory, it would | |
1726 | * make sense to do this. It will make moving the rest of the information | |
1727 | * a lot simpler! (Which we're not doing right now because we're not | |
1728 | * measuring them yet). | |
1729 | * | |
1da177e4 LT |
1730 | * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
1731 | * races with threads incrementing their own counters. But since word | |
1732 | * reads are atomic, we either get new values or old values and we don't | |
1733 | * care which for the sums. We always take the siglock to protect reading | |
1734 | * the c* fields from p->signal from races with exit.c updating those | |
1735 | * fields when reaping, so a sample either gets all the additions of a | |
1736 | * given child after it's reaped, or none so this sample is before reaping. | |
2dd0ebcd | 1737 | * |
de047c1b RT |
1738 | * Locking: |
1739 | * We need to take the siglock for CHILDEREN, SELF and BOTH | |
1740 | * for the cases current multithreaded, non-current single threaded | |
1741 | * non-current multithreaded. Thread traversal is now safe with | |
1742 | * the siglock held. | |
1743 | * Strictly speaking, we donot need to take the siglock if we are current and | |
1744 | * single threaded, as no one else can take our signal_struct away, no one | |
1745 | * else can reap the children to update signal->c* counters, and no one else | |
1746 | * can race with the signal-> fields. If we do not take any lock, the | |
1747 | * signal-> fields could be read out of order while another thread was just | |
1748 | * exiting. So we should place a read memory barrier when we avoid the lock. | |
1749 | * On the writer side, write memory barrier is implied in __exit_signal | |
1750 | * as __exit_signal releases the siglock spinlock after updating the signal-> | |
1751 | * fields. But we don't do this yet to keep things simple. | |
2dd0ebcd | 1752 | * |
1da177e4 LT |
1753 | */ |
1754 | ||
f06febc9 | 1755 | static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) |
679c9cd4 | 1756 | { |
679c9cd4 SK |
1757 | r->ru_nvcsw += t->nvcsw; |
1758 | r->ru_nivcsw += t->nivcsw; | |
1759 | r->ru_minflt += t->min_flt; | |
1760 | r->ru_majflt += t->maj_flt; | |
1761 | r->ru_inblock += task_io_get_inblock(t); | |
1762 | r->ru_oublock += task_io_get_oublock(t); | |
1763 | } | |
1764 | ||
1da177e4 LT |
1765 | static void k_getrusage(struct task_struct *p, int who, struct rusage *r) |
1766 | { | |
1767 | struct task_struct *t; | |
1768 | unsigned long flags; | |
0cf55e1e | 1769 | cputime_t tgutime, tgstime, utime, stime; |
1f10206c | 1770 | unsigned long maxrss = 0; |
1da177e4 LT |
1771 | |
1772 | memset((char *) r, 0, sizeof *r); | |
64861634 | 1773 | utime = stime = 0; |
1da177e4 | 1774 | |
679c9cd4 | 1775 | if (who == RUSAGE_THREAD) { |
e80d0a1a | 1776 | task_cputime_adjusted(current, &utime, &stime); |
f06febc9 | 1777 | accumulate_thread_rusage(p, r); |
1f10206c | 1778 | maxrss = p->signal->maxrss; |
679c9cd4 SK |
1779 | goto out; |
1780 | } | |
1781 | ||
d6cf723a | 1782 | if (!lock_task_sighand(p, &flags)) |
de047c1b | 1783 | return; |
0f59cc4a | 1784 | |
1da177e4 | 1785 | switch (who) { |
0f59cc4a | 1786 | case RUSAGE_BOTH: |
1da177e4 | 1787 | case RUSAGE_CHILDREN: |
1da177e4 LT |
1788 | utime = p->signal->cutime; |
1789 | stime = p->signal->cstime; | |
1790 | r->ru_nvcsw = p->signal->cnvcsw; | |
1791 | r->ru_nivcsw = p->signal->cnivcsw; | |
1792 | r->ru_minflt = p->signal->cmin_flt; | |
1793 | r->ru_majflt = p->signal->cmaj_flt; | |
6eaeeaba ED |
1794 | r->ru_inblock = p->signal->cinblock; |
1795 | r->ru_oublock = p->signal->coublock; | |
1f10206c | 1796 | maxrss = p->signal->cmaxrss; |
0f59cc4a ON |
1797 | |
1798 | if (who == RUSAGE_CHILDREN) | |
1799 | break; | |
1800 | ||
1da177e4 | 1801 | case RUSAGE_SELF: |
e80d0a1a | 1802 | thread_group_cputime_adjusted(p, &tgutime, &tgstime); |
64861634 MS |
1803 | utime += tgutime; |
1804 | stime += tgstime; | |
1da177e4 LT |
1805 | r->ru_nvcsw += p->signal->nvcsw; |
1806 | r->ru_nivcsw += p->signal->nivcsw; | |
1807 | r->ru_minflt += p->signal->min_flt; | |
1808 | r->ru_majflt += p->signal->maj_flt; | |
6eaeeaba ED |
1809 | r->ru_inblock += p->signal->inblock; |
1810 | r->ru_oublock += p->signal->oublock; | |
1f10206c JP |
1811 | if (maxrss < p->signal->maxrss) |
1812 | maxrss = p->signal->maxrss; | |
1da177e4 LT |
1813 | t = p; |
1814 | do { | |
f06febc9 | 1815 | accumulate_thread_rusage(t, r); |
1da177e4 LT |
1816 | t = next_thread(t); |
1817 | } while (t != p); | |
1da177e4 | 1818 | break; |
0f59cc4a | 1819 | |
1da177e4 LT |
1820 | default: |
1821 | BUG(); | |
1822 | } | |
de047c1b | 1823 | unlock_task_sighand(p, &flags); |
de047c1b | 1824 | |
679c9cd4 | 1825 | out: |
0f59cc4a ON |
1826 | cputime_to_timeval(utime, &r->ru_utime); |
1827 | cputime_to_timeval(stime, &r->ru_stime); | |
1f10206c JP |
1828 | |
1829 | if (who != RUSAGE_CHILDREN) { | |
1830 | struct mm_struct *mm = get_task_mm(p); | |
1831 | if (mm) { | |
1832 | setmax_mm_hiwater_rss(&maxrss, mm); | |
1833 | mmput(mm); | |
1834 | } | |
1835 | } | |
1836 | r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */ | |
1da177e4 LT |
1837 | } |
1838 | ||
1839 | int getrusage(struct task_struct *p, int who, struct rusage __user *ru) | |
1840 | { | |
1841 | struct rusage r; | |
1da177e4 | 1842 | k_getrusage(p, who, &r); |
1da177e4 LT |
1843 | return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
1844 | } | |
1845 | ||
e48fbb69 | 1846 | SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) |
1da177e4 | 1847 | { |
679c9cd4 SK |
1848 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
1849 | who != RUSAGE_THREAD) | |
1da177e4 LT |
1850 | return -EINVAL; |
1851 | return getrusage(current, who, ru); | |
1852 | } | |
1853 | ||
8d2d5c4a AV |
1854 | #ifdef CONFIG_COMPAT |
1855 | COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru) | |
1856 | { | |
1857 | struct rusage r; | |
1858 | ||
1859 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && | |
1860 | who != RUSAGE_THREAD) | |
1861 | return -EINVAL; | |
1862 | ||
1863 | k_getrusage(current, who, &r); | |
1864 | return put_compat_rusage(&r, ru); | |
1865 | } | |
1866 | #endif | |
1867 | ||
e48fbb69 | 1868 | SYSCALL_DEFINE1(umask, int, mask) |
1da177e4 LT |
1869 | { |
1870 | mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); | |
1871 | return mask; | |
1872 | } | |
3b7391de | 1873 | |
b32dfe37 CG |
1874 | static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd) |
1875 | { | |
2903ff01 | 1876 | struct fd exe; |
496ad9aa | 1877 | struct inode *inode; |
2903ff01 | 1878 | int err; |
b32dfe37 | 1879 | |
2903ff01 AV |
1880 | exe = fdget(fd); |
1881 | if (!exe.file) | |
b32dfe37 CG |
1882 | return -EBADF; |
1883 | ||
496ad9aa | 1884 | inode = file_inode(exe.file); |
b32dfe37 CG |
1885 | |
1886 | /* | |
1887 | * Because the original mm->exe_file points to executable file, make | |
1888 | * sure that this one is executable as well, to avoid breaking an | |
1889 | * overall picture. | |
1890 | */ | |
1891 | err = -EACCES; | |
496ad9aa | 1892 | if (!S_ISREG(inode->i_mode) || |
2903ff01 | 1893 | exe.file->f_path.mnt->mnt_flags & MNT_NOEXEC) |
b32dfe37 CG |
1894 | goto exit; |
1895 | ||
496ad9aa | 1896 | err = inode_permission(inode, MAY_EXEC); |
b32dfe37 CG |
1897 | if (err) |
1898 | goto exit; | |
1899 | ||
bafb282d KK |
1900 | down_write(&mm->mmap_sem); |
1901 | ||
1902 | /* | |
4229fb1d | 1903 | * Forbid mm->exe_file change if old file still mapped. |
bafb282d KK |
1904 | */ |
1905 | err = -EBUSY; | |
4229fb1d KK |
1906 | if (mm->exe_file) { |
1907 | struct vm_area_struct *vma; | |
1908 | ||
1909 | for (vma = mm->mmap; vma; vma = vma->vm_next) | |
1910 | if (vma->vm_file && | |
1911 | path_equal(&vma->vm_file->f_path, | |
1912 | &mm->exe_file->f_path)) | |
1913 | goto exit_unlock; | |
bafb282d KK |
1914 | } |
1915 | ||
b32dfe37 CG |
1916 | /* |
1917 | * The symlink can be changed only once, just to disallow arbitrary | |
1918 | * transitions malicious software might bring in. This means one | |
1919 | * could make a snapshot over all processes running and monitor | |
1920 | * /proc/pid/exe changes to notice unusual activity if needed. | |
1921 | */ | |
bafb282d KK |
1922 | err = -EPERM; |
1923 | if (test_and_set_bit(MMF_EXE_FILE_CHANGED, &mm->flags)) | |
1924 | goto exit_unlock; | |
1925 | ||
4229fb1d | 1926 | err = 0; |
2903ff01 | 1927 | set_mm_exe_file(mm, exe.file); /* this grabs a reference to exe.file */ |
bafb282d | 1928 | exit_unlock: |
b32dfe37 CG |
1929 | up_write(&mm->mmap_sem); |
1930 | ||
1931 | exit: | |
2903ff01 | 1932 | fdput(exe); |
b32dfe37 CG |
1933 | return err; |
1934 | } | |
1935 | ||
028ee4be CG |
1936 | static int prctl_set_mm(int opt, unsigned long addr, |
1937 | unsigned long arg4, unsigned long arg5) | |
1938 | { | |
1939 | unsigned long rlim = rlimit(RLIMIT_DATA); | |
028ee4be | 1940 | struct mm_struct *mm = current->mm; |
fe8c7f5c CG |
1941 | struct vm_area_struct *vma; |
1942 | int error; | |
028ee4be | 1943 | |
fe8c7f5c | 1944 | if (arg5 || (arg4 && opt != PR_SET_MM_AUXV)) |
028ee4be CG |
1945 | return -EINVAL; |
1946 | ||
79f0713d | 1947 | if (!capable(CAP_SYS_RESOURCE)) |
028ee4be CG |
1948 | return -EPERM; |
1949 | ||
b32dfe37 CG |
1950 | if (opt == PR_SET_MM_EXE_FILE) |
1951 | return prctl_set_mm_exe_file(mm, (unsigned int)addr); | |
1952 | ||
1ad75b9e | 1953 | if (addr >= TASK_SIZE || addr < mmap_min_addr) |
028ee4be CG |
1954 | return -EINVAL; |
1955 | ||
fe8c7f5c CG |
1956 | error = -EINVAL; |
1957 | ||
028ee4be CG |
1958 | down_read(&mm->mmap_sem); |
1959 | vma = find_vma(mm, addr); | |
1960 | ||
028ee4be CG |
1961 | switch (opt) { |
1962 | case PR_SET_MM_START_CODE: | |
fe8c7f5c CG |
1963 | mm->start_code = addr; |
1964 | break; | |
028ee4be | 1965 | case PR_SET_MM_END_CODE: |
fe8c7f5c | 1966 | mm->end_code = addr; |
028ee4be | 1967 | break; |
028ee4be | 1968 | case PR_SET_MM_START_DATA: |
fe8c7f5c | 1969 | mm->start_data = addr; |
028ee4be | 1970 | break; |
fe8c7f5c CG |
1971 | case PR_SET_MM_END_DATA: |
1972 | mm->end_data = addr; | |
028ee4be CG |
1973 | break; |
1974 | ||
1975 | case PR_SET_MM_START_BRK: | |
1976 | if (addr <= mm->end_data) | |
1977 | goto out; | |
1978 | ||
1979 | if (rlim < RLIM_INFINITY && | |
1980 | (mm->brk - addr) + | |
1981 | (mm->end_data - mm->start_data) > rlim) | |
1982 | goto out; | |
1983 | ||
1984 | mm->start_brk = addr; | |
1985 | break; | |
1986 | ||
1987 | case PR_SET_MM_BRK: | |
1988 | if (addr <= mm->end_data) | |
1989 | goto out; | |
1990 | ||
1991 | if (rlim < RLIM_INFINITY && | |
1992 | (addr - mm->start_brk) + | |
1993 | (mm->end_data - mm->start_data) > rlim) | |
1994 | goto out; | |
1995 | ||
1996 | mm->brk = addr; | |
1997 | break; | |
1998 | ||
fe8c7f5c CG |
1999 | /* |
2000 | * If command line arguments and environment | |
2001 | * are placed somewhere else on stack, we can | |
2002 | * set them up here, ARG_START/END to setup | |
2003 | * command line argumets and ENV_START/END | |
2004 | * for environment. | |
2005 | */ | |
2006 | case PR_SET_MM_START_STACK: | |
2007 | case PR_SET_MM_ARG_START: | |
2008 | case PR_SET_MM_ARG_END: | |
2009 | case PR_SET_MM_ENV_START: | |
2010 | case PR_SET_MM_ENV_END: | |
2011 | if (!vma) { | |
2012 | error = -EFAULT; | |
2013 | goto out; | |
2014 | } | |
fe8c7f5c CG |
2015 | if (opt == PR_SET_MM_START_STACK) |
2016 | mm->start_stack = addr; | |
2017 | else if (opt == PR_SET_MM_ARG_START) | |
2018 | mm->arg_start = addr; | |
2019 | else if (opt == PR_SET_MM_ARG_END) | |
2020 | mm->arg_end = addr; | |
2021 | else if (opt == PR_SET_MM_ENV_START) | |
2022 | mm->env_start = addr; | |
2023 | else if (opt == PR_SET_MM_ENV_END) | |
2024 | mm->env_end = addr; | |
2025 | break; | |
2026 | ||
2027 | /* | |
2028 | * This doesn't move auxiliary vector itself | |
2029 | * since it's pinned to mm_struct, but allow | |
2030 | * to fill vector with new values. It's up | |
2031 | * to a caller to provide sane values here | |
2032 | * otherwise user space tools which use this | |
2033 | * vector might be unhappy. | |
2034 | */ | |
2035 | case PR_SET_MM_AUXV: { | |
2036 | unsigned long user_auxv[AT_VECTOR_SIZE]; | |
2037 | ||
2038 | if (arg4 > sizeof(user_auxv)) | |
2039 | goto out; | |
2040 | up_read(&mm->mmap_sem); | |
2041 | ||
2042 | if (copy_from_user(user_auxv, (const void __user *)addr, arg4)) | |
2043 | return -EFAULT; | |
2044 | ||
2045 | /* Make sure the last entry is always AT_NULL */ | |
2046 | user_auxv[AT_VECTOR_SIZE - 2] = 0; | |
2047 | user_auxv[AT_VECTOR_SIZE - 1] = 0; | |
2048 | ||
2049 | BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); | |
2050 | ||
2051 | task_lock(current); | |
2052 | memcpy(mm->saved_auxv, user_auxv, arg4); | |
2053 | task_unlock(current); | |
2054 | ||
2055 | return 0; | |
2056 | } | |
028ee4be | 2057 | default: |
028ee4be CG |
2058 | goto out; |
2059 | } | |
2060 | ||
2061 | error = 0; | |
028ee4be CG |
2062 | out: |
2063 | up_read(&mm->mmap_sem); | |
028ee4be CG |
2064 | return error; |
2065 | } | |
300f786b | 2066 | |
52b36941 | 2067 | #ifdef CONFIG_CHECKPOINT_RESTORE |
300f786b CG |
2068 | static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr) |
2069 | { | |
2070 | return put_user(me->clear_child_tid, tid_addr); | |
2071 | } | |
52b36941 | 2072 | #else |
300f786b CG |
2073 | static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr) |
2074 | { | |
2075 | return -EINVAL; | |
2076 | } | |
028ee4be CG |
2077 | #endif |
2078 | ||
c4ea37c2 HC |
2079 | SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, |
2080 | unsigned long, arg4, unsigned long, arg5) | |
1da177e4 | 2081 | { |
b6dff3ec DH |
2082 | struct task_struct *me = current; |
2083 | unsigned char comm[sizeof(me->comm)]; | |
2084 | long error; | |
1da177e4 | 2085 | |
d84f4f99 DH |
2086 | error = security_task_prctl(option, arg2, arg3, arg4, arg5); |
2087 | if (error != -ENOSYS) | |
1da177e4 LT |
2088 | return error; |
2089 | ||
d84f4f99 | 2090 | error = 0; |
1da177e4 | 2091 | switch (option) { |
f3cbd435 AM |
2092 | case PR_SET_PDEATHSIG: |
2093 | if (!valid_signal(arg2)) { | |
2094 | error = -EINVAL; | |
1da177e4 | 2095 | break; |
f3cbd435 AM |
2096 | } |
2097 | me->pdeath_signal = arg2; | |
2098 | break; | |
2099 | case PR_GET_PDEATHSIG: | |
2100 | error = put_user(me->pdeath_signal, (int __user *)arg2); | |
2101 | break; | |
2102 | case PR_GET_DUMPABLE: | |
2103 | error = get_dumpable(me->mm); | |
2104 | break; | |
2105 | case PR_SET_DUMPABLE: | |
2106 | if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) { | |
2107 | error = -EINVAL; | |
1da177e4 | 2108 | break; |
f3cbd435 AM |
2109 | } |
2110 | set_dumpable(me->mm, arg2); | |
2111 | break; | |
1da177e4 | 2112 | |
f3cbd435 AM |
2113 | case PR_SET_UNALIGN: |
2114 | error = SET_UNALIGN_CTL(me, arg2); | |
2115 | break; | |
2116 | case PR_GET_UNALIGN: | |
2117 | error = GET_UNALIGN_CTL(me, arg2); | |
2118 | break; | |
2119 | case PR_SET_FPEMU: | |
2120 | error = SET_FPEMU_CTL(me, arg2); | |
2121 | break; | |
2122 | case PR_GET_FPEMU: | |
2123 | error = GET_FPEMU_CTL(me, arg2); | |
2124 | break; | |
2125 | case PR_SET_FPEXC: | |
2126 | error = SET_FPEXC_CTL(me, arg2); | |
2127 | break; | |
2128 | case PR_GET_FPEXC: | |
2129 | error = GET_FPEXC_CTL(me, arg2); | |
2130 | break; | |
2131 | case PR_GET_TIMING: | |
2132 | error = PR_TIMING_STATISTICAL; | |
2133 | break; | |
2134 | case PR_SET_TIMING: | |
2135 | if (arg2 != PR_TIMING_STATISTICAL) | |
2136 | error = -EINVAL; | |
2137 | break; | |
2138 | case PR_SET_NAME: | |
2139 | comm[sizeof(me->comm) - 1] = 0; | |
2140 | if (strncpy_from_user(comm, (char __user *)arg2, | |
2141 | sizeof(me->comm) - 1) < 0) | |
2142 | return -EFAULT; | |
2143 | set_task_comm(me, comm); | |
2144 | proc_comm_connector(me); | |
2145 | break; | |
2146 | case PR_GET_NAME: | |
2147 | get_task_comm(comm, me); | |
2148 | if (copy_to_user((char __user *)arg2, comm, sizeof(comm))) | |
2149 | return -EFAULT; | |
2150 | break; | |
2151 | case PR_GET_ENDIAN: | |
2152 | error = GET_ENDIAN(me, arg2); | |
2153 | break; | |
2154 | case PR_SET_ENDIAN: | |
2155 | error = SET_ENDIAN(me, arg2); | |
2156 | break; | |
2157 | case PR_GET_SECCOMP: | |
2158 | error = prctl_get_seccomp(); | |
2159 | break; | |
2160 | case PR_SET_SECCOMP: | |
2161 | error = prctl_set_seccomp(arg2, (char __user *)arg3); | |
2162 | break; | |
2163 | case PR_GET_TSC: | |
2164 | error = GET_TSC_CTL(arg2); | |
2165 | break; | |
2166 | case PR_SET_TSC: | |
2167 | error = SET_TSC_CTL(arg2); | |
2168 | break; | |
2169 | case PR_TASK_PERF_EVENTS_DISABLE: | |
2170 | error = perf_event_task_disable(); | |
2171 | break; | |
2172 | case PR_TASK_PERF_EVENTS_ENABLE: | |
2173 | error = perf_event_task_enable(); | |
2174 | break; | |
2175 | case PR_GET_TIMERSLACK: | |
2176 | error = current->timer_slack_ns; | |
2177 | break; | |
2178 | case PR_SET_TIMERSLACK: | |
2179 | if (arg2 <= 0) | |
2180 | current->timer_slack_ns = | |
6976675d | 2181 | current->default_timer_slack_ns; |
f3cbd435 AM |
2182 | else |
2183 | current->timer_slack_ns = arg2; | |
2184 | break; | |
2185 | case PR_MCE_KILL: | |
2186 | if (arg4 | arg5) | |
2187 | return -EINVAL; | |
2188 | switch (arg2) { | |
2189 | case PR_MCE_KILL_CLEAR: | |
2190 | if (arg3 != 0) | |
4db96cf0 | 2191 | return -EINVAL; |
f3cbd435 | 2192 | current->flags &= ~PF_MCE_PROCESS; |
4db96cf0 | 2193 | break; |
f3cbd435 AM |
2194 | case PR_MCE_KILL_SET: |
2195 | current->flags |= PF_MCE_PROCESS; | |
2196 | if (arg3 == PR_MCE_KILL_EARLY) | |
2197 | current->flags |= PF_MCE_EARLY; | |
2198 | else if (arg3 == PR_MCE_KILL_LATE) | |
2199 | current->flags &= ~PF_MCE_EARLY; | |
2200 | else if (arg3 == PR_MCE_KILL_DEFAULT) | |
2201 | current->flags &= | |
2202 | ~(PF_MCE_EARLY|PF_MCE_PROCESS); | |
1087e9b4 | 2203 | else |
259e5e6c | 2204 | return -EINVAL; |
259e5e6c | 2205 | break; |
1da177e4 | 2206 | default: |
f3cbd435 AM |
2207 | return -EINVAL; |
2208 | } | |
2209 | break; | |
2210 | case PR_MCE_KILL_GET: | |
2211 | if (arg2 | arg3 | arg4 | arg5) | |
2212 | return -EINVAL; | |
2213 | if (current->flags & PF_MCE_PROCESS) | |
2214 | error = (current->flags & PF_MCE_EARLY) ? | |
2215 | PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE; | |
2216 | else | |
2217 | error = PR_MCE_KILL_DEFAULT; | |
2218 | break; | |
2219 | case PR_SET_MM: | |
2220 | error = prctl_set_mm(arg2, arg3, arg4, arg5); | |
2221 | break; | |
2222 | case PR_GET_TID_ADDRESS: | |
2223 | error = prctl_get_tid_address(me, (int __user **)arg2); | |
2224 | break; | |
2225 | case PR_SET_CHILD_SUBREAPER: | |
2226 | me->signal->is_child_subreaper = !!arg2; | |
2227 | break; | |
2228 | case PR_GET_CHILD_SUBREAPER: | |
2229 | error = put_user(me->signal->is_child_subreaper, | |
2230 | (int __user *)arg2); | |
2231 | break; | |
2232 | case PR_SET_NO_NEW_PRIVS: | |
2233 | if (arg2 != 1 || arg3 || arg4 || arg5) | |
2234 | return -EINVAL; | |
2235 | ||
2236 | current->no_new_privs = 1; | |
2237 | break; | |
2238 | case PR_GET_NO_NEW_PRIVS: | |
2239 | if (arg2 || arg3 || arg4 || arg5) | |
2240 | return -EINVAL; | |
2241 | return current->no_new_privs ? 1 : 0; | |
2242 | default: | |
2243 | error = -EINVAL; | |
2244 | break; | |
1da177e4 LT |
2245 | } |
2246 | return error; | |
2247 | } | |
3cfc348b | 2248 | |
836f92ad HC |
2249 | SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep, |
2250 | struct getcpu_cache __user *, unused) | |
3cfc348b AK |
2251 | { |
2252 | int err = 0; | |
2253 | int cpu = raw_smp_processor_id(); | |
2254 | if (cpup) | |
2255 | err |= put_user(cpu, cpup); | |
2256 | if (nodep) | |
2257 | err |= put_user(cpu_to_node(cpu), nodep); | |
3cfc348b AK |
2258 | return err ? -EFAULT : 0; |
2259 | } | |
10a0a8d4 JF |
2260 | |
2261 | char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff"; | |
2262 | ||
2ca067ef | 2263 | static int __orderly_poweroff(bool force) |
10a0a8d4 | 2264 | { |
b57b44ae | 2265 | char **argv; |
10a0a8d4 JF |
2266 | static char *envp[] = { |
2267 | "HOME=/", | |
2268 | "PATH=/sbin:/bin:/usr/sbin:/usr/bin", | |
2269 | NULL | |
2270 | }; | |
b57b44ae | 2271 | int ret; |
10a0a8d4 | 2272 | |
2ca067ef ON |
2273 | argv = argv_split(GFP_KERNEL, poweroff_cmd, NULL); |
2274 | if (argv) { | |
2275 | ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC); | |
2276 | argv_free(argv); | |
2277 | } else { | |
10a0a8d4 | 2278 | printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n", |
2ca067ef ON |
2279 | __func__, poweroff_cmd); |
2280 | ret = -ENOMEM; | |
10a0a8d4 JF |
2281 | } |
2282 | ||
2ca067ef ON |
2283 | if (ret && force) { |
2284 | printk(KERN_WARNING "Failed to start orderly shutdown: " | |
2285 | "forcing the issue\n"); | |
2286 | /* | |
2287 | * I guess this should try to kick off some daemon to sync and | |
2288 | * poweroff asap. Or not even bother syncing if we're doing an | |
2289 | * emergency shutdown? | |
2290 | */ | |
2291 | emergency_sync(); | |
2292 | kernel_power_off(); | |
2293 | } | |
10a0a8d4 | 2294 | |
b57b44ae AM |
2295 | return ret; |
2296 | } | |
2297 | ||
2ca067ef ON |
2298 | static bool poweroff_force; |
2299 | ||
2300 | static void poweroff_work_func(struct work_struct *work) | |
2301 | { | |
2302 | __orderly_poweroff(poweroff_force); | |
2303 | } | |
2304 | ||
2305 | static DECLARE_WORK(poweroff_work, poweroff_work_func); | |
2306 | ||
b57b44ae AM |
2307 | /** |
2308 | * orderly_poweroff - Trigger an orderly system poweroff | |
2309 | * @force: force poweroff if command execution fails | |
2310 | * | |
2311 | * This may be called from any context to trigger a system shutdown. | |
2312 | * If the orderly shutdown fails, it will force an immediate shutdown. | |
2313 | */ | |
2314 | int orderly_poweroff(bool force) | |
2315 | { | |
2ca067ef ON |
2316 | if (force) /* do not override the pending "true" */ |
2317 | poweroff_force = true; | |
2318 | schedule_work(&poweroff_work); | |
2319 | return 0; | |
10a0a8d4 JF |
2320 | } |
2321 | EXPORT_SYMBOL_GPL(orderly_poweroff); | |
4a22f166 SR |
2322 | |
2323 | /** | |
2324 | * do_sysinfo - fill in sysinfo struct | |
2325 | * @info: pointer to buffer to fill | |
2326 | */ | |
2327 | static int do_sysinfo(struct sysinfo *info) | |
2328 | { | |
2329 | unsigned long mem_total, sav_total; | |
2330 | unsigned int mem_unit, bitcount; | |
2331 | struct timespec tp; | |
2332 | ||
2333 | memset(info, 0, sizeof(struct sysinfo)); | |
2334 | ||
2335 | ktime_get_ts(&tp); | |
2336 | monotonic_to_bootbased(&tp); | |
2337 | info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0); | |
2338 | ||
2339 | get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT); | |
2340 | ||
2341 | info->procs = nr_threads; | |
2342 | ||
2343 | si_meminfo(info); | |
2344 | si_swapinfo(info); | |
2345 | ||
2346 | /* | |
2347 | * If the sum of all the available memory (i.e. ram + swap) | |
2348 | * is less than can be stored in a 32 bit unsigned long then | |
2349 | * we can be binary compatible with 2.2.x kernels. If not, | |
2350 | * well, in that case 2.2.x was broken anyways... | |
2351 | * | |
2352 | * -Erik Andersen <andersee@debian.org> | |
2353 | */ | |
2354 | ||
2355 | mem_total = info->totalram + info->totalswap; | |
2356 | if (mem_total < info->totalram || mem_total < info->totalswap) | |
2357 | goto out; | |
2358 | bitcount = 0; | |
2359 | mem_unit = info->mem_unit; | |
2360 | while (mem_unit > 1) { | |
2361 | bitcount++; | |
2362 | mem_unit >>= 1; | |
2363 | sav_total = mem_total; | |
2364 | mem_total <<= 1; | |
2365 | if (mem_total < sav_total) | |
2366 | goto out; | |
2367 | } | |
2368 | ||
2369 | /* | |
2370 | * If mem_total did not overflow, multiply all memory values by | |
2371 | * info->mem_unit and set it to 1. This leaves things compatible | |
2372 | * with 2.2.x, and also retains compatibility with earlier 2.4.x | |
2373 | * kernels... | |
2374 | */ | |
2375 | ||
2376 | info->mem_unit = 1; | |
2377 | info->totalram <<= bitcount; | |
2378 | info->freeram <<= bitcount; | |
2379 | info->sharedram <<= bitcount; | |
2380 | info->bufferram <<= bitcount; | |
2381 | info->totalswap <<= bitcount; | |
2382 | info->freeswap <<= bitcount; | |
2383 | info->totalhigh <<= bitcount; | |
2384 | info->freehigh <<= bitcount; | |
2385 | ||
2386 | out: | |
2387 | return 0; | |
2388 | } | |
2389 | ||
2390 | SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info) | |
2391 | { | |
2392 | struct sysinfo val; | |
2393 | ||
2394 | do_sysinfo(&val); | |
2395 | ||
2396 | if (copy_to_user(info, &val, sizeof(struct sysinfo))) | |
2397 | return -EFAULT; | |
2398 | ||
2399 | return 0; | |
2400 | } | |
2401 | ||
2402 | #ifdef CONFIG_COMPAT | |
2403 | struct compat_sysinfo { | |
2404 | s32 uptime; | |
2405 | u32 loads[3]; | |
2406 | u32 totalram; | |
2407 | u32 freeram; | |
2408 | u32 sharedram; | |
2409 | u32 bufferram; | |
2410 | u32 totalswap; | |
2411 | u32 freeswap; | |
2412 | u16 procs; | |
2413 | u16 pad; | |
2414 | u32 totalhigh; | |
2415 | u32 freehigh; | |
2416 | u32 mem_unit; | |
2417 | char _f[20-2*sizeof(u32)-sizeof(int)]; | |
2418 | }; | |
2419 | ||
2420 | COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info) | |
2421 | { | |
2422 | struct sysinfo s; | |
2423 | ||
2424 | do_sysinfo(&s); | |
2425 | ||
2426 | /* Check to see if any memory value is too large for 32-bit and scale | |
2427 | * down if needed | |
2428 | */ | |
2429 | if ((s.totalram >> 32) || (s.totalswap >> 32)) { | |
2430 | int bitcount = 0; | |
2431 | ||
2432 | while (s.mem_unit < PAGE_SIZE) { | |
2433 | s.mem_unit <<= 1; | |
2434 | bitcount++; | |
2435 | } | |
2436 | ||
2437 | s.totalram >>= bitcount; | |
2438 | s.freeram >>= bitcount; | |
2439 | s.sharedram >>= bitcount; | |
2440 | s.bufferram >>= bitcount; | |
2441 | s.totalswap >>= bitcount; | |
2442 | s.freeswap >>= bitcount; | |
2443 | s.totalhigh >>= bitcount; | |
2444 | s.freehigh >>= bitcount; | |
2445 | } | |
2446 | ||
2447 | if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) || | |
2448 | __put_user(s.uptime, &info->uptime) || | |
2449 | __put_user(s.loads[0], &info->loads[0]) || | |
2450 | __put_user(s.loads[1], &info->loads[1]) || | |
2451 | __put_user(s.loads[2], &info->loads[2]) || | |
2452 | __put_user(s.totalram, &info->totalram) || | |
2453 | __put_user(s.freeram, &info->freeram) || | |
2454 | __put_user(s.sharedram, &info->sharedram) || | |
2455 | __put_user(s.bufferram, &info->bufferram) || | |
2456 | __put_user(s.totalswap, &info->totalswap) || | |
2457 | __put_user(s.freeswap, &info->freeswap) || | |
2458 | __put_user(s.procs, &info->procs) || | |
2459 | __put_user(s.totalhigh, &info->totalhigh) || | |
2460 | __put_user(s.freehigh, &info->freehigh) || | |
2461 | __put_user(s.mem_unit, &info->mem_unit)) | |
2462 | return -EFAULT; | |
2463 | ||
2464 | return 0; | |
2465 | } | |
2466 | #endif /* CONFIG_COMPAT */ |